<u>Answer</u>:
x = 7, y = 2
<u>Explanation</u>:
equations given:
x + 7y = 21
x + 4y = 15
make "x" the subject:
x + 7y = 21
x = 21 - 7y .........equation 1
x + 4y = 15
x = 15 - 4y .......equation 2
Solving both the equations simultaneously:
15 - 4y = 21 - 7y
-4y + 7y = 21 - 15
3y = 6
y = 6 ÷ 3
y = 2
If y is 2
Then x = 21 -7y;
x = 21 - 7(2)
x = 21 - 14
x = 7
Answer: 10 inches × 14 inches
Work:
length = x inches
width = x - 4 inches
perimeter = 2(l+w)
48 = 2[(x)+(x - 4)]
48 = 2(2x - 4)
24 = 2x - 4
28 = 2x
14 = x
length = x inches = 14 inches
width = x - 4 inches = 14 - 4 = 10 inches
This simplified is 126x so that is equivalent to this expression
1) 50x30
2) 2000+409
3) 500+800