7 gallons of pure acid and 14 gallons of 10% acid
7x-4=52 is correct because he made 7 times more than Jack which is 7x. For example if Jack made 8 decorations, 7 x (8) = 56. If you subtract 4 from 56 you get 52. Therefore, the equation 7x-4=52 is correct.
Consider the right triangle ABC with legs AB=4, AC=3 and hypotenuse BC=5. Angle B has
and
.
Since O lies in second quadrant
and
.
Answer: 
.
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.
