X=2y-6;y=3x-7
substitution to solve systems of equations

As you said, we can solve this system for y by using substitution.

Now, using what we got for y, we plug it into one of the original equations to solve for x.

Now we have the solution of this system.

b. 24 mm

step-by-step explanation:

use the pythagorean theorem.

a^2 + b^2 = c^2

a^2 + 7^2 = 25^2

a^2 + 49 = 625

a^2 = 576

a = 24

answer: b. 24 mm