Jack bought 3 slices of cheese pizza and 4 sclices of mushroom pizza for $12.50. Grace bought 3 slices of cheese pizza and 2 slices of mushroom pizza for $8.50. What is the cost of 1 slice of mushroom pizza?
A) $1.50 B) $2.00 C)$3.00 D)$3.50

Question

Jack bought 3 slices of cheese pizza and 4 sclices of mushroom pizza for $12.50. Grace bought 3 slices of cheese pizza and 2 slices of mushroom pizza for $8.50. What is the cost of 1 slice of mushroom pizza?
A) $1.50  B) $2.00  C)$3.00  D)$3.50

anonymous · Answer

If 'x' is a cheese slice, 'y' is a mushroom slice you need to solve the set of equations:
(1) 3x + 4y = 12.5
(2) 3x + 2y = 8.5
And find how much is 'y'

Add (-2y) to both sides of equation (2) to get:
3x = 8.5 - 2y
And then substitute it into the equation (1)
(8.5 - 2y) + 4y = 12.5

anonymous · Answer

aliter to    adamshai 's work
(1) 3x + 4y = 12.5
 (2) 3x + 2y = 8.5
since coefficient of x are equal 
just subtract eq 2 from eq 1
we get 2y=4
or y=2


the cost of 1 slice of mushroom pizza is B) $2.00