Calculate Triangle Height PQ Given Area 30 cm² and Base 4 cm

Question

PRS is a triangle.

The length of side SR is 4 cm.
The area of triangle PSR is 30 cm².

Calculate the height PQ.

00:11 Let's calculate the height P Q.

00:14 Look at the lengths of the sides and lines using the given data.

00:18 Now, use the formula to find the area of a triangle.

00:26 It's height times base, all divided by two.

00:31 Plug in the values and solve for P Q.

00:39 Multiply by the denominators to clear any fractions.

00:49 Now, isolate P Q on one side.

01:05 And that's how we find the solution!

We use the formula to calculate the area of the triangle.

Pay attention: in an obtuse triangle, the height is located outside of the triangle!

$\frac{Side\cdot Height}{2}=\text{Triangular Area}$

Double the equation by a common denominator:

$\frac{4\cdot PQ}{2}=30$

$\cdot2$

Divide the equation by the coefficient of $PQ$ .

$4PQ=60$ / $:4$

$PQ=15$

15 cm