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Odiasharoldgo
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21. The area of triangle varies jointly as the base and the height. A triangle with a base of 6cm
and a height of 14cm has an area of 42 square centimeters. Find the area when the base is
4cm and the height is 9 cm.
a. 16 cm2
b. 18cm
c. 20 cm
d. 22cm
​

Sagot :

Pepgee82go

Answer:

b. 18 cm.

Step-by-step explanation:

Let:

A = area

b = base

h = height

k = constant

Formula of joint variation:

y = kxz

so, A = kbh

Use the values to find the constant k first.

42 = k (6)(14)

^ ^ ^

A b h

42 = 84k

42/84 = k

½ = k

Then, use the constant to find the Area.

A = ½ (4)(9)

= ½ (36)

A = 18 cm.

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