Question
x+2y=10
2x - y = 5
The solution to the given system of equations is (x, y). What is the value of 3x + y ?
- 5
- 7
- 13
- 15
The correct answer is: 15
Given equations
x + 2y = 10 ______ (1)
2x - y = 5 ________ (2)
Multiply equation (1) with 2 on both sides
(2x - y) 2 = 5 2
4x - 2y = 10 ______ (3)
Add equation (1) & (3)
x + 2y + 4x - 2y = 10 + 10
5x = 20
x = 4
Substitute x value in the equation (1)
x + 2y = 10
4 + 2y = 10
2y = 6
y = 3
3x + y = 3(4) + 3
= 12 + 3
= 15
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When a buffet restaurant charges $12.00 per meal, the number of meals it sells per day is 400. For each $0.50 increase to the price per meal, the number of meals sold per day decreases by 10. What is the price per meal that results in the greatest sales, in dollars, from meals each day?
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1.) The rate is frequently stated as a percentage.
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When a buffet restaurant charges $12.00 per meal, the number of meals it sells per day is 400. For each $0.50 increase to the price per meal, the number of meals sold per day decreases by 10. What is the price per meal that results in the greatest sales, in dollars, from meals each day?
Discount is the term used to describe the sum or portion subtracted from an item's usual selling price — a good or service's price decreases when given a discount. For instance, if the item breaks, we can ask the manager for a discount.
When a bond's price is expected to be less than its face value, it is known as a discount. Discounts are a form of product cost price reduction or deduction. When customers receive discounts on various things, it is frequently employed in consumer transactions. How to Find Discount
1.) The rate is frequently stated as a percentage.
2.) To calculate the discount, we must multiply the rate by the starting cost.
3.) To calculate the sale price, we must subtract the discount from the purchase price.
¶ Rate of Discount = Discount% = Discount List / Price×100.