Examples with solutions for Parabola of the form y=x²: Finding a stationary point

Exercise #1

What is the value of y for the function?

y=x2 y=x^2

of the point x=2 x=2 ?

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Substitute the given value of x x into the equation.
  • Step 2: Perform the calculation to find y y .

Now, let's work through each step:
Step 1: The given equation is y=x2 y = x^2 . We need to substitute x=2 x = 2 into this equation.

Step 2: Substitute to get y=(2)2 y = (2)^2 . Calculate 2×2=4 2 \times 2 = 4 .

Therefore, the value of y y when x=2 x = 2 is y=4 y = 4 .

Hence, the solution to the problem is y=4 y = 4 .

Answer

y=4 y=4

Exercise #2

What is the value of X for the function?

y=x2 y=x^2

of the point y=4 y=4 ?

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Set the equation of the function with the given point, x2=4 x^2 = 4 .
  • Step 2: Solve for x x by taking the square root of both sides. This accounts for both the positive and negative solutions.
  • Step 3: Evaluate the expression to find the solutions.

Now, let's work through each step:
Step 1: Set up the equation based on the given information:
We have x2=4 x^2 = 4 .

Step 2: Solve by taking the square root of both sides:
Taking the square root, we get x=±4 x = \pm\sqrt{4} .

Step 3: Simplify to find the values of x x :
The square root of 4 is 2, thus x=2 x = 2 and x=2 x = -2 .

Therefore, the solutions for x x are x=2 x = 2 and x=2 x = -2 .

The correct answer is choice Answers a + b, which corresponds to having solutions x=2 x = 2 and x=2 x = -2 .

Answer

Answers a + b

Exercise #3

What is the value of X for the function?

y=x2 y=x^2

of the point y=16 y=16 ?

Video Solution

Step-by-Step Solution

To solve this problem, let's find the steps required to determine x x when y=16 y = 16 in the function y=x2 y = x^2 :

  • Step 1: Substitute the given y y into the equation to get x2=16 x^2 = 16 .
  • Step 2: To solve x2=16 x^2 = 16 , take the square root of both sides, remembering to include both positive and negative roots. This yields x=±16 x = \pm\sqrt{16} .
  • Step 3: Simplify to find x=±4 x = \pm4 , which gives the solutions x=4 x = 4 and x=4 x = -4 .

Thus, the value(s) of x x that satisfy y=16 y = 16 in the function y=x2 y = x^2 are x=4 x = 4 and x=4 x = -4 .

Therefore, the solution to the given problem is x=4,x=4 x = 4, x = -4 .

Answer

x=4,x=4 x=4,x=-4

Exercise #4

What is the value of X for the function?

y=x2 y=x^2

of the point y=36 y=36 ?

Video Solution

Step-by-Step Solution

To solve the problem, we will proceed with the following steps:

  • Identify the provided equation and condition.
  • Apply the square root property to solve the equation.
  • Verify the solution with the given choices.

Step-by-step solution:

Step 1: Substitute y=36 y = 36 into the equation y=x2 y = x^2 , which gives:

x2=36 x^2 = 36

Step 2: Solve for x x by taking the square root of both sides. Using the square root property, we have:

x=±36 x = \pm \sqrt{36}

Since the square root of 36 is 6, we find that:

x=±6 x = \pm 6

Therefore, the solutions to the equation are x=6 x = 6 and x=6 x = -6 .

Thus, the value of x x for y=36 y = 36 in the function y=x2 y = x^2 is x=±6 x = \pm 6 .

Answer

x=±6 x=\pm6

Exercise #5

What is the value of y for the function?

y=x2 y=x^2

of the point x=6 x=6 ?

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify the value given for x x .
  • Step 2: Substitute the given x x value into the function.
  • Step 3: Calculate the resulting value for y y .

Now, let's work through each step:
Step 1: The problem states that x=6 x = 6 .
Step 2: Using the function y=x2 y = x^2 , we substitute x=6 x = 6 .
Step 3: Perform the calculation: y=62 y = 6^2 .

Calculating 62 6^2 , we get 36 36 .
Therefore, for the function y=x2 y = x^2 , when x=6 x = 6 , the value of y y is y=36 y = 36 .

Answer

y=36 y=36

Exercise #6

What is the value of X for the function?

y=x2 y=x^2

of the point y=25 y=25 ?

Video Solution

Step-by-Step Solution

Let's solve the problem by following these steps:

  • Step 1: Identify the equation to solve.
  • Step 2: Apply the square root to both sides of the equation.
  • Step 3: Solve for both positive and negative values of x x .

Step 1: We start with the equation derived from the function:
x2=25 x^2 = 25

Step 2: To isolate x x , we take the square root of both sides. Remember, the square root of a number can be both positive and negative:
x=±25 x = \pm \sqrt{25}

Step 3: Simplify the square root:
x=±5 x = \pm 5 , which means x=5 x = 5 or x=5 x = -5

Therefore, the values of x x that satisfy y=25 y = 25 in the function y=x2 y = x^2 are x=5 x = 5 and x=5 x = -5 .

Looking at the choices given, the correct answer is:

x=5,x=5 x=5,x=-5

Answer

x=5,x=5 x=5,x=-5

Exercise #7

What is the value of X for the function?

y=x2 y=x^2

of the point y=8 y=8 ?

Video Solution

Step-by-Step Solution

The problem requires us to find the value of x x for the function y=x2 y = x^2 when y=8 y = 8 .

Let's solve this step-by-step:

  • Step 1: Set up the equation based on the given function:
     y=x2\ y = x^2 becomes  x2=8\ x^2 = 8 .
  • Step 2: Solve for x x by taking the square root of both sides:

Since  x2=8\ x^2 = 8 , we take the square root of both sides to find x x :

x=±8 x = \pm\sqrt{8}

Step 3: Simplify the square root:

The square root of 8 can be simplified to  8=4×2=42=22\ \sqrt{8} = \sqrt{4 \times 2} = \sqrt{4} \cdot \sqrt{2} = 2\sqrt{2} .

Thus,  x=±22\ x = \pm 2\sqrt{2} .

Therefore, the solution is x=±22 x = \pm 2\sqrt{2} , which corresponds to choice 4.

Answer

x=±22 x=\pm2\sqrt{2}

Exercise #8

What is the value of y for the function?

y=x2 y=x^2

of the point x=10 x=10 ?

Video Solution

Step-by-Step Solution

To find the value of y y for the function y=x2 y = x^2 at the point where x=10 x = 10 , we will follow these steps:

  • Step 1: Identify the function, which is y=x2 y = x^2 .
  • Step 2: Substitute x=10 x = 10 into the function.
  • Step 3: Perform the calculation to find y y .

Now, let's work through each step:
Step 1: We have the function y=x2 y = x^2 .
Step 2: Substitute x=10 x = 10 into the equation: y=(10)2 y = (10)^2 .
Step 3: Calculate the result: y=10×10=100 y = 10 \times 10 = 100 .

Therefore, the value of y y for the function when x=10 x = 10 is y=100 y = 100 .

Answer

y=100 y=100

Exercise #9

What is the value of y for the function?

y=x2 y=x^2

of the point x=7 x=7 ?

Video Solution

Step-by-Step Solution

To find the value of y y when x=7 x = 7 in the function y=x2 y = x^2 , we will follow these straightforward steps:

  • Step 1: Substitute x=7 x = 7 into the function. Therefore, y=(7)2 y = (7)^2 .
  • Step 2: Calculate the value of 72 7^2 . The expression 72 7^2 means 7×7 7 \times 7 .
  • Step 3: Perform the multiplication. 7×7=49 7 \times 7 = 49 .

Thus, when x=7 x = 7 , the value of y y is 49 49 .

Therefore, the value of y y at x=7 x = 7 is y=49 y = 49 .

Answer

y=49 y=49

Exercise #10

What is the value of y for the function?

y=x2 y=x^2

of the point x=12 x=12 ?

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify the given information.
  • Step 2: Apply the appropriate formula by substituting the given value.
  • Step 3: Perform the calculation to find the solution.

Let's work through each step:

Step 1: The function is given by y=x2 y = x^2 and the value of x x is 12.

Step 2: Substitute x=12 x = 12 into the function. We have:

y=122 y = 12^2 .

Step 3: Calculate the square of 12:

122=144 12^2 = 144 .

Therefore, the value of y y at the point x=12 x = 12 is y=144 y = 144 .

Comparing this with the multiple-choice answers, the correct choice is:

  • Choice 4: y=144 y = 144 .

Thus, the final answer is y=144 y = 144 .

Answer

y=144 y=144