Answer:
Step-by-step explanation:
3a-8a>-20
-5a>-20
a>-20/-5
a>4
6x + 4y = 12...subtract 6x from both sides
4y = -6x + 12 ...divide both sides by 4
(4/4)y = (-6/4)x + 12/4...reduce
y = -3/2x + 4 <== y = mx + b
ANSWER

EXPLANATION
Recall that,

That is why

is equivalent to

This implies that,

This is the same as,

When we are dividing by

we move the decimal point backwards two times.
This implies that,
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