If ABCD congruent to QRST, measure of angle A = x - 10º, and measure of angle Q = 2x - 30º, what is the measure of angle A?

Congruent means they are the same,

A and Q are both the first letters, which mean they would also be the same.

Set the two equations equal to each other, solve for x then solve for angle A.

x-10 = 2x-30

Add 30 to each side:

x+20 = 2x

Subtract 1x from each side:

x = 20

Now replace x with 20 in the equation for A

A = 20-10

Angle A = 10 degrees.