jessica and castel each improved their yards by planting daylilies and ornamental grass. they bought their supplies from the same store. jessica spent $47 dollars on 2 daylillies and 3 bunches of ornamental grass. Castel spent $87 on 6 daylilies and 3 bunches of ornamental grass. find the cost of one daylily and the cost of one bunch of ornamental grass.
This is two equations two variables. Let x be the cost of 1 bunch daylillies and y be the cost of 1 bunch of ornamental grass. So 2x + 3y = 47 and 6x + 3y = 87 Do you understand so far?
yes
Put those on top of each other (one above the other) The idea is to get rid of one of the letters. so we should have a 3y over a 3y. If the bottom one was -3y we could add them up and they would go away. So. let's change the sign of every term on the bottom. 2x + 3y = 47 -6x - 3y = -87 OK so far?
yes
So add straight down and you get -4x = -40 Divide both sides by -4 and you get x = 10 Plug that into one of the equations and solve for y 2x + 3y = 47 2(10) + 3y = 47 20 + 3y = 47 subtract 20 from both sides 3y = 27 divide both sides by 3 y = 9 So the cost of one daylilly was $10 (because x = 10) The cost of one ornamental was $9 (because y = 9)
oo okay
thanku
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