106k views
2 votes
How do you work this equation? x² + x - 30 = 0

User Gunwin
by
3.4k points

2 Answers

6 votes

Answer:

(x-5) (x+6)

x=5

X=-6

Explanation:

x²+x-30=0

factorizing

x²-5x+6x-30=0

x(x-5)+6(x-5) =0

(x-5)(x+6)=0

now solve individually

x-5=0

send 5 to the other side

x=5

x+6=0

send 6 to the other side

x=-6

hope you understand the procedure

User Valay
by
3.3k points
2 votes

Answer:

x = 5 , x = - 6

Explanation:

First we factor using factorisation method :

We need 2 numbers that multiply to give +1 and add to give -30 :

To find these numbers we write out all the factors of 30 :

1, 30

2 , 15

3 , 10

5 , 6 ----> These must be the numbers as -5+6 = 1

Now we split +x into -5x and +6x :

x² -5x + 6x -30 = 0

Factor the first 2 terms together and the last two terms :

x(x-5) + 6(x-5) = 0

Keep 1 bracket and terms outside the brackets collect them into one:

(x-5)(x+6) = 0

We know that 1 of these brackets must be equal to zero as anything multiplied by zero = 0

Either x - 5 =0 OR x + 6 = 0

So x = 5 x = - 6

These are our final answers

Hope this helped and have a good day

User Aet
by
2.9k points