This is an area of rectangle equation. You take the base(b) and you multiply it with the Height(h) your equation should look like this :
A=b*h. You substitute the dimensions and get A=50*9 which A=450 sq blocks.
It’s 25 because (24x24)+(7x7) squared is 25
Complementary angles add up to 90 so 90-29=the complement, which is 61.
You haven't included enough information for the question, but assuming that a and b are the same then a is 4 and b is 4