The length of a rectangle is 10 cm. If its perimeter is 28 cm, find the area
30cm2
40cm2
60cm2
80cm2
Correct answer is B
perimeter = 2( length + breadth)
→ 28 = 2 (10+ b)
14 - 10 = b
b = 4
Area = length x breadth
10 x 4 → 40cm2
In the diagram, ∠ZWZY and WYX are right angles. Find the perimeter of WXYZ.
30cm
32cm
35cm
37cm
Correct answer is B
In ΔWYZ:
hyp2 = adj2 + opp2
hyp2 =32 + 42 → 9 + 16
hyp2 = 25
hyp = 5
In ΔWXY:
hyp2 = adj2 + opp2
hyp2 = 122 + 52 = 144 +25
hyp2 = 169
hyp = 13
the perimeter of WXYZ. = 3+4+12+13 → 32cm