Let x = your number.
x^2 - 21 = 4x. Subtract 4x from both sides.
x^2 - 4x - 21 = 0. Factor.
(x - 7) (x + 3) = 0. Set each term to 0.
x + 3 = 0. Subtract 3 from both sides.
x = -3. This is the negative solution.
Set the other term equal to zero.
x - 7 = 0. Add 7 to each side.
x = 7. This is the positive solution.
10 cakes can be made
Explanation:
Convert 7 1/2 to an improper fraction
15/2 divided by 3/4
Flip the second fraction and multiply instead of divide
15/2 x 4/3
multiply the tops: 15 x 4 = 60
Over the bottoms multiplied together 2x3=6
60/6=10
therefore 10 cakes can be made
22^4=22x22x22x22
22^7=22x22x22x22x22x22x22
This means that 22^7 is greater and by the amount of 22^3
Answer:
56.52 cm³
Step-by-step explanation:

Diameter= 2 ×radius
Radius
= 6 ÷2
= 3cm
Height, h= 6cm
Volume of the cone

= 56.52 cm³