Question

Which equation would be help solve the following problem? The height of a triangle is 5m less than its base. The area of the triangle is 42m^2.
Find the length of the base?


42=x(x-5)

42=1/2(x)(x-5)

42=x^2-5

42=1/2(x^2-5)

First correct answer will make brainliest

Answer 1

Answer:

Part 1) $42=\frac{1}{2}x(x-5)$

Part 2) The length of the base is $x=12\ m$

Step-by-step explanation:

Part 1) Which equation would be help solve the following problem?

Let

x----> the length of the base of a triangle

y----> the height of a triangle

we know that

The area of a triangle is

$A=\frac{1}{2}xy$

$A=42\ m^{2}$

so

$42=\frac{1}{2}xy$ ------> equation A

$y=x-5$ -----> equation B

Substitute equation B in equation A  

$42=\frac{1}{2}x(x-5)$

Part 2) Find the length of the base

we have

$42=\frac{1}{2}x(x-5)$

solve for x

$84=x^{2}-5x\\x^{2}-5x-84=0$

Solve the quadratic equation by graphing

The solution is $x=12\ m$

see the attached figure