You have to do 21+8+11=40. So 40 is the answer. Hope this helps.
If you divide a fraction over a number, you can just muplitply the denominator (the number under the line) by the number by which you divide:

99 and 21 are divisible by 3, so we can divide them both by it:

but that's all we can do!
so let's multiply

and it's its simplest form
Answer:
x = (y - b)/m
Step-by-step explanation:
Isolate the variable, x. Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS.
First subtract b from both sides:
y = mx + b
y (-b) = mx + b (-b)
y - b = mx
Next, divide m from both sides:
(y - b)/m = (mx)/m
x = (y - b)/m
x = (y - b)/m is your answer.
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ANSWER

EXPLANATION
Use the Pythagoras Theorem to obtain,

This implies that,


Take the positive square root of both sides to get,

