Answer:
5 feet.
Step-by-step explanation:
Please find the attachment.
Let x be the length of ramp.
We have been given that a ramp extends from the back of a truck bed to the ground. The back of the truck bed is 4 feet above the ground. The horizontal distance from the spot below the back of the truck bed to the bottom of the ramp is 3 feet.
We can see from our attachment that ramp and the height of truck bed form a right triangle, so the length of ramp will be equal to hypotenuse of right triangle with two legs of 4 feet and 3 feet.
We will use Pythagorean theorem to solve for the length of ramp.
[tex]x^2=4^2+3^2[/tex]
[tex]x^2=16+9[/tex]
[tex]x^2=25[/tex]
Upon taking square root of both sides of our equation we will get,
[tex]x=\pm 5[/tex]
Since length of ramp can not be negative, therefore, length of ramp will be 5 feet.