Answer:
2p + 4b = 42
7p + 9b = 107
p = $5
b = $8
Explanation:
p is cost of plant, b is cost of bush
2p + 4b = 42
7p + 9b = 107
First we'll solve the first equation for p in terms of b:
2p + 4b = 42
subtract 4b from both sides
2p = -4b + 42
divide both sides by 2
p = -2b + 21
Now substitute that value in for p in the second equation, and solve for a numerical value of b:
7(-2b + 21) + 9b = 107
-14b + 147 + 9b = 107
combine like terms:
-5b = -40
b = 8
Use this to go back and solve for p:
p = -2b + 21
p = -2(8) + 21
p = -16 + 21 = 5
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check the math:
2p + 4b = 42
2(5) + 4(8) = 10 + 32 = 42