Umm. Is this high school?.
4 friends x 2 ballons = 8 friends only ballons.
8 + 1 = 9.
9 total
<ADC = <BAD = 115
hope it helps
10
sum is add
cube is to the 3rd powr
19+x³
11.
product means multiply
3 times y is no more than (equal to or less than ) 21
3y≤21
no need to solve
12. 2 times difference is 10
difference is subtract
2(z-12)=10