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5 votes
5r^2 - 44r + 120 = -30 + 11r
solve the quadratic equations by factoring

User Sanket Ray
by
6.5k points

2 Answers

3 votes
make on side 0
because if ab=0 then assume a and b=0

so first minus 11r from both sides


5r²-55r+120=-30
divide both sides by 5 for convenience
r²-11r+24=-6
add 6 to both sides
r²-11r+30=0
factor
what 2 numbres multiply to get 30 and add to get -11
-6 and -5
(r-6)(r-5)=0
set each equal to 0

r-6=0
r=6

r-5=0
r=5


r=5 and 6
User Jay Kumo
by
6.3k points
3 votes
Hey I hope this helps you
You first need to move everything to one side to equal zero.
Then factor out the 5
After you should be left with a quadratic equation easier to work with
What multiplies to 30 and adds to -11?
This would be 6 and 5
But since it is -11 those two numbers need to be negative as well
5r^2 - 44r + 120 = -30 + 11r solve the quadratic equations by factoring-example-1
User FrankM
by
5.6k points