50 feet
It is 10 feet from -10ft to 0ft, plus 40ft to the roof.
Multply both sides of the equation by 7.

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When the variable is in the numerator of a proportion like this, you can solve it by multiplying by that denominator. That multiplication cancels the denominator and gives you the value of the variable.
In general, you multiply by the reciprocal of the coefficient of x. When that coefficient is 1/7, you multiply by 7/1. Of course, you know that 7/7 = 1 and that x/1 = x.
Answer:
(a) 
(b) 
Step-by-step explanation:
It is given that 
(a) We have given equation 



(b) 



Answer:
41.88
Step-by-step explanation:
3.49*12=41.88