Answer:
a) Cost of a chicken shawarma wrap?
$10.99
b) Cost of one order of spiced potatoes?
$4.99
Explanation:
Cost of a chicken sharwarma wrap = a
Cost of an order of spiced potatoes = b
Ms. Ironperson ordered 3 chicken shawarma wraps and 2 orders of spiced potatoes for a total bill of $42.95.
3a + 2b = $42.95 .............Equation 1
Mr. Thoro ordered 5 chicken shawarma wraps and 4 orders of spiced potatoes for a total bill of $74.91.
5a + 4b = $74.91 ................Equation 2
So we have:
3a + 2b = $42.95 .............Equation 1
5a + 4b = $74.91 ................Equation 2
We use Elimination method to solve for this.
Multiply Equation 1 by coefficient of b in Equation 2
Equation 2 by coefficient of b in Equation 1
3a + 2b= $42.95 .............Equation 1 × 4
5a + 4b = $74.91 ................Equation 2 × 2
12a + 8b = 171.80..............Equation 3
10a + 8b = 149.82..............Equation 4
Subtract Equation 3 from Equation 4
2a = 21.98
a = 21.98/2
a = 10.99
Therefore, a = Cost of Chicken sharwarma wrap = $10.99
Subtitute 10.99 for 9in Equation 1
3a + 2b = $42.95 .............Equation 1
3(10.99) + 2b = 42.95
32.97 + 2b = 42.95
2b = 42.95 - 32.97
2b = 9.98
b = 9.98/2
b = 4.99
b = Cost of an order of spiced potatoes = $4.99
Hence,
The cost of a chicken sharwarma wrap = $10.99
The cost of an order of spiced potatoes = $4.99