Find the values of x and y in the following rectangle [see Fig. ].
Solution:
We know that opposite sides of a rectangle are equal
3x + y = 7 … (1)
x + 3y = 13 … (2)
Find the value of x and y using elimination method in equation (1) and (2)
9x + 3y = 21 {Multiply (1) by 3}
x + 3y = 13
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8x = 8
x = = 1
Put x = 1 in equation (1)
3(1) + y = 7
3 + y = 7
y = 7 – 3
y = 4