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4 votes
Solve the Quadratics:

1) k^2-8k=0
2) a^2+5a=0
3) 6n^2+5n-25=0
4) 2x^2-11x-21=0
5) 2n^2+13n+19=4


Bonus Word Problem:

The larger leg of a right triangle is 7cm longer than its smaller leg. The hypotenuse is 8cm longer than the small leg. How many centimeters long is the smaller leg?

User Louisa
by
7.1k points

1 Answer

2 votes

Answer:

Explanation:

1 ) k²-8k = 0

k(k-8)=0

k = 0 or k=8

2) a²+5a=0

a(a+5) = 0

a=0 or a = - 5

3 ) 6n²+5n-25=0

delta = b²-4ac b =5 and a = 6 and c= - 25

delta = 5²-4(6)(-25) = 625 = 25²

n 1 = (-5+25)/12 = 20/12 = 5/3

n 2 = (-5-25)/12 = - 30/12 = -5/2

same method for 4) and 5)

User Marzelin
by
7.2k points
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