Answer:
area of a triangle is 1/2×h×b
Step-by-step explanation:
1÷2×12×13
=78
180cm^2 & 472ft^2
answer of 16 number
h2=p2+b2 ,therefore
h=100+80
h=180
answer of question 17
h2=p2+b2
576=p2+104
576-104=p2
472=p2
