Answer:
m∠XMN = 80°
Step-by-step explanation:
you know that:
4x + 5 + 6x - 10 = 145
solve for x:
10x - 5 = 145
10x = 150
x = 15
Use this information to solve for m∠XMN
6(15) - 10
90 - 10
80
m∠XMN = 80°
The answer is 12y+30.
Twice the width would be 10+4y, so the length is 10+4y.
To find the perimeter, we can do 2(5+2y) + 2(10+4y).
That equals 10+4y+20+8y.
Which, equals 12y+30.