Exercise 60 Page 42

The area of a triangle is half of the product of the base, b, and the height, h.

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The right triangle shown below has an area of 5h square centimeters.

The area of a triangle is half of the product of the base, b, and the height, h. A=1/2 b h ⇒ 5h=1/2 h(2h) We need to solve the equation for h.

5h=1/2h(2h)

5h=2h^2/2

Calculate quotient

5h=h^2

LHS-h^2=RHS-h^2

5h-h^2=0

Factor out h

h(5-h)=0

To solve this equation, we will apply the Zero Product Property.

h(5-h)=0

Use the Zero Product Property

lch=0 & (I) 5-h=0 & (II)

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(II): Solve for h

(II): LHS-5=RHS-5

lch=0 & (I) - h=- 5 & (II)

(II): .LHS /(- 1).=.RHS /(- 1).

lch=0 & (I) h=5 & (II)

The base of the triangle is 5 cm and the height of it is 10cm. Therefore, the answer is D. h= 5 & 2h= 10

Exercises p.39-42

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