Answer:
x = -2, y=1
Step-by-step explanation:
x-7y=-9---------------------equation 1
-x+8y=10-------------------equation 2
From equation 1, make x the subject of formula
x=7y-9----------------------equation 3
substituting x=7y-9 in equation 2,
-(7y-9)+8y=10
Expanding bracket
-7y+9+8y=10
Collecting like terms
8y-7y=10-9
y=1
substituting y=1 in 3
x=7(1)-9
x=7-9
x=-2
Answer:
1. 30
2. 34
Step-by-step explanation:
2(4(3) + 3)
2(12 + 3)
2(15)
= 30
12(3) - 2
36 - 2
= 34
hope this helps :)
4 fries + 6 cheeseburgers = $52
3 fries + 2 cheeseburgers = $24
9 fries + 6 cheeseburgers = $24×3
= $72
$72-$52=$20
5 fries = $20
1 fries = $20÷5
= $4
1 cheeseburger = [$24 - (3×$4)]÷2
= $6
