Answer:
20
Step-by-step explanation:
The two given and marked angles add up to 90.
A = x
B = 3x + 10
A + B = 90 Substitute for A and B. A and B are just letters I gave things.
x + 3x + 10 = 90 Combine the left
4x + 10 = 90 Subtract 10 from both sides.
4x +10-10 = 90-10 Combine
4x = 80 Divide by 4
4x/4=80/4
x = 20
Answer:
Step-by-step explanation:
5x = 2x + 9
3x = 9
x = 3
AB= 5(3)= 15
BC= 2(5) + 9= 10 + 9 = 19
AC= 15 + 19 = 34
Answer:
D. AAA is not a congruence postulate
Step-by-step explanation: