Question

Solve the following word problem by using an equation and factoring. Write the solution only in the blank.

The sum of a positive number and its square is 20. What is the number?

Answer 1

i would guess and check on this one

\[3^2+3=12\] too small
try 4

Answer 2

4 is too big .

Answer 3

it's -5

Answer 4

actually i think 4 is just rigth

Answer 5

upps.. positive, fail

Answer 6

\[4+4^2=4+16=20\]

Answer 7

4 is right ! :)

a^2 + a -20 = 0.

Solve for a, you get 4 and -5. You get the positive one!