13.) A=9cm^2
If the area is l•h, and there are 9 cubic squares, that means that the length of each side on the square is 3cm, each square on it equals 1cm.
14.) V=27cm^3
If the volume is l•w•h, then we find the third power square root of 27, so 3•3=9•3=27, the answer is 3cm for the length, width, and height.
15.) V=4,913cm^3
If volume is l•w•h, then what number when raised to the third power equals 4913? The answer is 17, since 17•17=289•17=4913. So the length is 17cm
16.)V=216cm^3
If volume is l•w•h, then what number when raised to the third power equals 216? The answer is 6, since 6•6=36•6=216.
17.)A=121
Is area is l•w, then what number raised to the second power equals 121? The answer is 11, since 11•11=121. Therefore it WILL NOT fit a car with a length of 13ft.
18.)A=141
If area is l•w, then what number raised to the second power equals 141? The answer is 12, since 11.87•11.87=141 (answer was rounded to nearest whole number) meaning that she will need 12ft of fence to enclose her garden.
If you have at least as many equations as your have unknown variables, the 'system' is solvable (unless the equations are copies of eachother).
In this case, isolate one letter and plug it in the other. I'm going for the 2a in the bottom one (it doesn't matter)
2a - 4b = 12 => (divide by two and move the b's to the other side)
a = 6 + 2b. (plug this one into the top equation)
4(6+2b) + 6b = 10 => 24+8b+6b = 10 => 24 + 14b = 10 => 14b = -14 => b=-1
a = 6 + -2 = 4.
So a=4 and b=-1.
I believe C is your answer.
I hope this helps!
Answer:
81cm
Step-by-step explanation:
15cm + 20cm + 21cm + 25cm = 81cm
