Solve the following equation:
2x2+x−4=0
To solve the equation 2x2+x−4=0, we'll use the quadratic formula. First, we need to rewrite the equation in standard quadratic form, ax2+bx+c=0.
Start by multiplying the entire equation by 2 to eliminate the fraction:
x2+2x−8=0
Now, identify the coefficients:
- a=1
- b=2
- c=−8
Next, plug these coefficients into the quadratic formula:
x=2a−b±b2−4ac
Substitute a=1, b=2, and c=−8 into the formula:
x=2⋅1−2±22−4⋅1⋅(−8)
Simplify inside the square root first:
22−4⋅1⋅(−8)=4+32=36
Substitute back:
x=2−2±36
The square root of 36 is 6, so:
x=2−2±6
Calculate the two possible solutions:
1.
x1=2−2+6=24=2
2.
x2=2−2−6=2−8=−4
Therefore, the solutions for the equation 2x2+x−4=0 are x1=2 and x2=−4.
x1=2,x2=−4