Given that a√b^2-c = 5k, find the value of:

1. k when a = 3, b = 6 and c = 20
2. c when a = 4, b = 7, and k = 11

Explain your working please

4 answers

Are sure that the equation is NOT
a√(b^2-c) = 5k ?

or else the way you have it, it would simply become
ab -c = 5k

So I will assume it is a√(b^2-c) = 5k

I will do the 2nd, you do the first

2.
a√(b^2-c) = 5k
4√49-c) = 55
√(49-c) = 55/4
square both sides
49-c = 3025/16
-c = 3025/16 - 49
-c = 2241/16
c = - 2241/16
Is the formula correct? √b^2? That's just b

However, if you mean √(b^2-c) then just plug in the numbers!

5k = 3*√(36-20) = 3*4 = 12

not so hard, eh?
√b^2 = b

Therefore, the equation is really:

ab - c = 5k

Insert values and calculate.
Very bad to finish