Answer: Irons cost = $310
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Step-by-step explanation:
r = cost of irons
w = cost of woods
These costs are in dollars. They are some positive real number.
The irons cost $90 more than the woods, so r = w+90
The total cost is $530, leading to r+w = 530
We can apply substitution to solve for w
r+w = 530
(r) + w = 530
(w+90) + w = 530 .... replace r with w+90
w+90+w = 530
w+w+90 = 530
2w+90 = 530
2w+90-90 = 530-90 ... subtract 90 from both sides
2w = 440
2w/2 = 440/2 .... divide both sides by 2
w = 220
A set of woods golf clubs cost $220
This must mean
r = w+90
r = 220+90
r = 310
The set of irons cost $310
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Check:
(woods cost)+(irons cost) = (220) + (310) = 530
This confirms the answer.