x = 5 and y = 6
Solution:
IJKL is a rectangle.
<em>In rectangle, opposite sides are equal.</em>
JK = IL
3x + 21 = 6y
Subtract 21 from both sides.
3x = 6y – 21
Divide by 3 on both sides, we get
x = 2y – 7 ---------- (1)
<em>In rectangle, opposite sides are equal.</em>
JI = KL
6y – 6 = 2x + 20
Substitute (1) in above equation, we get
6y – 6 = 2(2y – 7) + 20
6y – 6 = 4y – 14 + 20
6y – 6 = 4y + 6
Subtract 4y from both sides.
2y – 6 = 6
Add 6 on both sides.
2y = 12
y = 6
Substitute y = 6 in (1)
x = 2(6) – 7
x = 5
Hence x = 5 and y = 6.
First we find the price of 1 granola bar:
$3.15 / 7 granola bars = $0.45 per granola bar
13 granola bars * $0.45 each = x
13 * 0.45 = $5.85
x = $5.85
The transitive property is used. Its the property that if a = b and b = c, then a = c. You can think of it as linking a chain together.