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5 votes
Please solve this simultaneous equation, i'm not that good at it.

2r-s=10
rs-s^2=12

User Azikiwe
by
4.6k points

1 Answer

5 votes

Answer:

s = 6, r = 8 or s = 4, r = 7

Explanation:

2r - s = 10

2r = 10 + s

r = 5 + s/2 --(1)

rs - s^2 = 12 --(2)

sub (1) into (2):

(5 + s/2)s - s^2 = 12

5s + 0.5s^2 - s^2 = 12

-0.5s^2 + 5s - 12 = 0

s^2 - 10s + 24 = 0

(s - 6)(s - 4) = 0

therefore s = 6 or s = 4

when s = 6, r = 8 and when s = 4, r = 7

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User Zuleyka
by
4.9k points
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