Answer:
x = 20 but see below.
Explanation:
Remark.
This is not well enough marked to know whether D = A or whether you have to do some algebra to find the relationship between A and D. So I will assume A = D and then I'll solve it so you have to manipulate A and D.
A = D
3x - 10 = 2x + 10 Add 10 to both sides
3x - 10 + 10 = 2x + 10 + 10 Cancel
3x = 2x + 20 Subtract 2x from both sides
3x-2x=2x-2x + 20
x = 20
A = E
If A = E then to find x you have to add 3 angles together.
E + D + 45 = 180 Add the three angles of the triangle
E + D = 180 - 45 Subtract 45 from both sides
E + D = 135 Substitute for D and E
3x - 10 + 2x + 10 = 135 Combine like terms
5x = 135 Divide by 5
x = 135 / 5
x = 27
Answer
I'd go with the first one.