Answer:
(-2,3)
Step-by-step explanation:
Step 1. Isolate x for 3x + 5y = 9
3x + 5y - 5y = 9 - 5y
3x = 9 - 5y
3x/3 = 9/3 - 5y/3
x= (9-5y)/3
Step 2. Simplify
-3*((9-5y)/3) + 3y = 15
-3*((9-5y)/3) = 9 - 5y = -(-5 + 9) + 3y
-9+5y+3y
-9+8y = 15
Step 3 Isolate y for -9+8y=15
-9+8y+9=15+9
8y=24
8y/8 = 24/8
y=3
Step 4 Substitute y = 3
x = (9-5*3)/3
-(6/3) = (-2)
x = -2
The answer would be 6. 21/3.5=6
The area of the wall is figured by length * width.
Area of wall = 13*9=117 square feet
Since one can covers only 50 square feet you will not have enough with one can. You will need 117/50=2.34 cans. Assuming you can only buy full cans you would need to buy 3 cans.
