Answer:
a
Step-by-step explanation:
5 times 8 =40
It's a right triangle as it has the 90 degree corner and 3 different lengths
C. 4x + y = 21
4(3) + 9 = 21
12 + 9 = 21
21 = 21
This really depends on the fraction; if there are variables in the equation, if they are full numbers,etc. I'd really recommend looking up khan academy on YouTube and that will really help you out!
