A garden is given to have the shape of a right triangle with a hypothenuse length of 7m and a leg of length 5m. It is required to find the total cost of fencing if fencing cost $2.50/m.
To do this, find the missing length of leg, calculate the perimeter of the garden, and then multiply the perimeter by the cost of fencing per meter.
Recall the Pythagorean Theorem:

Where a and b are the lengths of the legs of the right triangle, and c is the length of the hypothenuse.
Let the missing length be b.
Substitute a=5 and c=7 into the equation:

Solve the equation for b:

Next, find the Perimeter of the garden by adding the side lengths:

Multiply the perimeter by the cost per meter to get the total cost of fencing:

The total cost of fencing is $42.25.