9. In parellelogram MRST, m<M=3x-40 and m<S=7x-100. Find:

a. the value of x.

b.the measure of <R

Are angle M and S congruent? If so, 3x-40=7x-100.

yes they are

thanks

To find the value of x, we'll set the two given angle measures equal to each other and solve for x.

a.
Given: m<M = 3x - 40 and m<S = 7x - 100

Since opposite angles in a parallelogram are congruent, we can set up the equation:

3x - 40 = 7x - 100

Let's solve for x:

3x - 7x = -100 + 40

-4x = -60

Dividing both sides by -4:

x = (-60) / (-4) = 15

So, the value of x is 15.

b.
To find the measure of angle R, we can substitute the value of x back into one of the angle measures and solve for the measure of angle R.

m<M = 3x - 40

m<M = 3(15) - 40

m<M = 45 - 40

m<M = 5

Therefore, the measure of angle R is 5 degrees.