Exercise 49 Page 402

Let's calculate the perimeter and area separately.

Perimeter

The perimeter of a figure is the sum of the side lengths. For a triangle, this is the sum of sides a, b, and c. P=a+b+c Since two of the given triangle's sides have matching tick-marks they are congruent. Thus, it is an isosceles triangle. If we let a be the length of one of the congruent sides and b be the length of the third side, we can write the perimeter of this triangle. P=2a+b To calculate P, we should substitute the given values, a=13yd and b=5yd+5yd=10yd, into the formula and simplify.

P=2a+b

SubstituteII

a= 13, b= 10

P=2( 13)+ 10

Multiply

Multiply

P=26+10

AddTerms

Add terms

P=36

The triangle's perimeter is 36 yards.

Area

Here we will use the formula for calculating the area of a triangle. A=1/2bh Now we substitute the value of the base, b=10, and the value of the height, h=12, into the formula to calculate A.

A=1/2bh

SubstituteII

b= 10, h= 12

A=1/2( 10)( 12)

MoveRightFacToNum

a/c* b = a* b/c

A=10/2* 12

CalcQuot

Calculate quotient

A=5* 12

Multiply

Multiply

A=60

The area of the triangle is 60yd^2.