What does #(3a-b)/(2a+b)# equal when #a=4# and #b=3#?
1 Answer
When
Explanation:
In order to evaluate this expression properly, we must remember two things: (1) the order of operations, and (2) how to treat variables when they have coefficients.
The expression is
So how do we get a value for
Here's how the substitution looks:
#color(white)(=" ") 3a-b#
#=3(4)-3#
And now simplifying:
#=12-3#
#=9#
The same procedure is done to find the value of
#color(white)(=" ")2a+b#
#=2(4)+3#
#=8+3#
#=11#
Normally, these two simplifications would be done at the same time, since neither one affects the other until the division needs to be done. So, we would simplify the whole expression like this:
#(3a-b)/(2a+b)=(3(4)-3)/(2(4)+3)=(12-3)/(8+3)=9/11#
That's as far as you should need to go. However, if you prefer a decimal expansion, this answer can be written as:
#9/11=0.stackrel_(81)=0.818181...#