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3 years ago

Need help with maths ASAP

Mathematics

1 answer:

givi [52]3 years ago

8 0

Answer:

a = 7

b = 3

Step-by-step explanation:

So you can come up with 2 equations.

a(9 + b) = 84

ab = 21

On the first equation, divide by 9 + b on both sides.

$a=\frac{84}{9+b}$

n the second equation, divide by b on both sides.

$a=\frac{21}{b}$

Now you can set them equal and solve for b.

$\frac{84}{9+b}=\frac{21}{b}$

Cross multiply:

84b = 189 + 21b

63b = 189

b = 3

a = 7

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