D, hope this is right! :)
Answer:
124 tiles
Step-by-step explanation:
2(20+40)
2(60)
120+4=124
Cuz if so, then you just move the whole x term to the right side and divide all the terms on the right side by the coefficient of y
for ex...
3) 4x+4y=16
4y=16-4x (or -4x+16)
y=4-x or -x+4
28 .to explain they want to know the missing side and the triangles are equal to each-other just one is projected smaller than the other . So the one with 16 16 and 24 is the smaller one . The difference between 24-16 is 8 . And In the bigger one the sides 20 and 20 where given so since the smaller one is equal to the bigger one you just do 20+8=28
