The question can be solved by simply making an equation with the information given:
$35 per hour
$90 to start because of the parts
$265 overall
We can make the following equation out of this:
35x + 90 = 265
From here, just solve for x:
35x = 175 Subtract 90 from both sides.
x = 5 Divide both sides by 35 to isolate the x variable.
Therefore, the mechanic expects the job to take 5 hours to complete.
Hope this helps! :)
EDIT 1: I tried to post this as a comment, but it didn't let me, so I'll just update this.
Question 2:
For the second question, you can make another equation with the given information. For the purpose of the equation, lets say A, B, and C are the lengths of each of the 3 corresponding sections. A and B are the same length, whilst C is double. This can be put into the equation:
A + B + 2A = 60
But because we know A = B, we can make it
2A + 2A = 60
4A = 60
From here, just divide both sides by 4, giving you
A = 15
B is the same, so
B = 15
and C is double, so
C = 30.
Just to rephrase for clarity: A = 15 B = 15 C = 30.
Again, hope this helps, and have a great day! :)
EDIT 2:
Question 3: For the third question, the following information is given:
96 feet overall (perimeter)
length = 16 + 3w
Like the previous two times, we make an equation with the given information. I would use substitution, which in this case I substituted the length for what we defined it as (REMEMBER: the equation of a rectangle is 2l + 2w = p; don't forget to multiply the length and width by 2):
2(16 + 3w) + 2w = 96
Now simplify the parentheses (distribute the 2):
32 + 6w + 2w = 96
8w = 64
w = 8
Now that we know the width is 8, all we need to do is plug it in to the equation for length we made:
length = 16 + 3(8)
length = 16 + 24
l = 40
Therefore, the dimensions of the garden are 40 x 8; in other words, length is 40 and width is 8.
If you want to check, just plug 40 and 8 into 2l + 2w = 96:
2(40) + 2(8) = 96
80 + 16 = 96
96 = 96 It works!
For a third time, hope this helps, and have a great day/night! :)