Answer:
Part A)
Part B)
Step-by-step explanation:
We know that the rectangle has a length of (x+5) and a width of 12 cm.
Part A)
Remember the formula for the perimeter of a rectangle:
We know that the perimeter is 86. Substitute that for P:
Substitute (x+5) for the length l and 17 for w. So:
We can simplify this to acquire our equation:
Part B)
To find the length, let's find our x first. We have the equation:
Divide both sides by 2:
Now, subtract 22 from both sides. Therefore, our x is:
To find the length, remember that the length is:
Since we now know the value of x, substitute 21 for x:
Add:
So, the length is 26 centimeters.
And we're done!