Question

Solve each quadratic equation. Show your work.
x^2 + 3x = 10

Answer 1

x^2 + 3x - 10 = 0
you need to find 2 numbers which when multiplied give -10 and when added give + 3

Answer 2

then these go into 2 brackets as below
(x + __)(x _ __)

Answer 3

think about the factors of -10

Answer 4

what comes to mind?

Answer 5

2 and 5

Answer 6

right - nearly there but its -10 not 10

Answer 7

its either -2 and 5 or -5 and 2 right?

Answer 8

which pair add up to +3 ?

Answer 9

-2 and 5

Answer 10

thats right so we write

(x + 5)(x - 2) = 0

can you continue ?

Answer 11

these are the factors of x^2 + 3x - 10
- now when 2 things are multiplied to give zero either one or the other must equal 0
so we have

x + 5 =0 and x - 2 = 0

so we only have to solve these 2 small equations and we our answer

these equations have 2 roots

Answer 12

* quadratic equations have 2 roots

Answer 13

so the answer is 2 or wat

Answer 14

x - 2 = 0 so x = 2
x+5 = 0 so x = -5

the solution set is {-2,5}

Answer 15

oh ok thanks alot

Answer 16

yw