This is 6th grade math not no 0.1428571432312323231231232131125467e+ collage math

Answer:
The length of h is 3cm.
Step-by-step explanation:
You are looking for h. In order to find h you need the equation of area of a triangle, which is a=1/2bh. They give you base and they give you area. Plugging the numbers in, the equation is 7 7/8 cm^2= 1/2(5 1/4)(h). Now you solve by getting h by itself.
2(7 7/8 cm^2)= (1/2(5 1/4)(h))2
(15 3/4)/(5 1/4)= ((5 1/4)(h))/(5 1/4)
3=h