At Home Depot, Johnny bought 3 rose bushes and 7 flats of petunias for a total of $114.75. Rosie bought 2 rose bushes and 6 flats of petunias for a total of $89.50. How

much does a rose bush cost? How much does a flat of petunias cost?

Step-by-step explanation:

At Home Depot, Johnny bought 3 rose bushes and 7 flats of petunias for a total of  $114.75.

Let x = rose bushes

Let y = petunias

This means;

3x + 7y = 114.75 (i)

Rosie bought 2 rose bushes and 6 flats of petunias for a total of $89.50.

2x + 6y = 89.50 (ii)

How  much does a rose bush cost? How much does a flat of petunias cost?

Multiply eqn (i) by 2 and eqn (ii) by 3.

This results too;

6x + 14y = 229.5 (iii)

6x + 18y = 268.5 (iv)

Subtract eqn (iii) from eqn (iv)

This results to;

4y = 39

y = 39 / 4 = $9.75

Subt the vale of y in eqn ii

2x = 89.50 - 6y

x = (89.50 - 6y) / 2

x = (89.50 - 6(39 / 4)) / 2

x = 31 / 2 = $15.5