Question

A triangle has an area of 90 cm. Find the length of the base if the base is 3 cm more than height.
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Answer 1

Answer:

length =15 cm

base = 15 cm

Answer 2

Step-by-step explanation:

area of a triangle =1/2 ×b×h

let the height be x

therefore, the base is x+3

90 =1/2 ×x×x+3

=1/2 ×x square +3x

therefore, 2×90=x square +3x

180= x square+3 x

x square +3 x -180 =0

x square +15x - 12 x +180=0

x(x+15) - 12 (x-15) =0

therefore, (x-12) =0 or (x+15)=0

x=12 or x=-15

length =x+3

length of the base =12 +3 = 15 or

-15+3 = -12

length of the base is -12 or 15 length of the base of the triangle cannot be negative therefore, 15 is the answer