Question

In ∆ABC, in which ^A=90, AB=4cm and BC=5cm, the perimeter of ∆ABC is​

Answer 1

ANSWER: 12cm.

As, angle A is 90 degree and AB=4cm, BC=5cm abd we should AC by phthagarous therom so we get it as:

[a*a]+[b*b]=[c*c]

[a*a]+[4*4]=[5*5]

[a*a]+16=25

[a*a]=25-16

[a*a]=9

a=3.

so, AC is 3cm.

Perimeter is AB+BC+AC

=4+5+3

=12CM is the answer.

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