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$32 $2 If we are paid by the hour, the more hours we work the more we are paid. This is an example of direct proportion. Our salary would be figured as y=kx where k is the constant of proportionality or our hourly rate. If we make $8 per hour, it becomes y=$8x. x would be the number of hours worked. y would be our pay. If we worked 4 hours, we would be paid y = $8(4) or... $40 $4 110 miles 200 miles If we make $8 per hour, it becomes y=$8x. x would be the number of hours worked. If we worked 4 hours, we would be paid $8 x 4 or $32.
Directly proportional y = kx works for many situations such as if we are traveling 55 m.p.h. and have traveled two hours we have gone 110 miles. What would we have gone after 4 hours? y = kx where k equals 55 m.p.h for this problem. So y = 55(4)... 55 miles 220 miles 280 miles 70 miles Traveling 55 m.p.h. what would we have gone after 4 hours? 55 m.p.h. is the constant. So 55 x 4 = 220.
The constant of proportionality (rate we are traveling per hour) changes in different problems. If we travel 70 miles per hour, what would we travel in 3 hours? 210 miles 220 miles xy = k If we travel 70 miles per hour, what would we travel in 3 hours? 70 x 3 = 210 miles.
The constant of porportionally stays the same for the problem such as miles per hour or dollars per hour. The formula for direct variation is y = kx. What is the formula for direct variation? y = kx y = x k y= $55k The formula for direct variation is y = kx.
If it costs $55 per day to rent a car, what is the formula to solve? y = $55x $55 = kx $55 If it costs $55 per day to rent a car, what is the formula to solve? $55 is the constant of proportionality. So the formula is y= $55x.
How much would 3 days be? $110 $165 $10 How much would 3 days be? y = $55x; therefore y = $55 x 3; $165.
Inverse variation would be if we agreed to do a job for a set price. The quicker we get done, the more money we make per the hour. An example would be raking a yard for $50. If it only takes us one hour, we make $50 per hour. If it takes two hours, we make $25 per hour. If it takes four hours, how much would we make per hour? $20 $15 $12.50 y = kx What if it takes four hours? $50 ÷ 4 = $12.50.
Find the formula for inverse variation. The formula for inverse variation is xy = k or .... y = k x kx = y xy = k xk = y y = Find the formula for inverse variation. The formula for inverse variation is xy = k or
If we know the area of a rectangle but not the length and width, the area would be the k or constant of proportionality. So if the area is 24 units squared, which formula is correct? y = 24 x x k y = 24 x y = 24x 3 = If the area is 24 units squared, which formula is correct? The area is constant of proportionality so it replaces k in the formula xy = k or
If the area is 24 square units and the length is 8, what is the width? y = x k 24 8 3 = 24 8 3 = 24(8) |