Examples with solutions for Area of a Triangle: Calculating in two ways

Exercise #1

The area of triangle ABC is equal to 56 cm².

BD = 7 cm

BC = 423 4\frac{2}{3} cm

Calculate the lengths of side AC and height AE.

777AAACCCBBBEEEDDD

Video Solution

Answer

AC = 16
AE = 24

Exercise #2

Shown below is the the triangle DEF.

FE = 8 cm

DE = 4 cm

FH = 25 cm

Calculate the height DG and the area of the triangle DEF.

444888252525DDDEEEFFFHHHGGG

Video Solution

Answer

DG =1 2.5, S=50

Exercise #3

DEF is a right triangle.

Height GE is 10 cm.
The area of DEF is 40 cm².

Calculate the length of side DF.

S=40S=40S=40101010DDDEEEFFFGGG

Video Solution

Answer

8 cm