Question

Anyone know how to do this? If so plz help

Answer 1

NOTES:

Use the equation y = mx + b where m is the unit rate and b is the one-time flat fee

1. Answer:

`\begin {array}cx&0&1&2&3\\ y&70.00&70.20&70.40&70.60\\\end{array}`

Explanation:

coffee maker costs $70 - this is a one-time flat fee

it costs $0.20 per cup of coffee - this is the unit rate

y = 0.20x + 70

y = 0.20(0) + 70 → y = 0.00 + 70 → y = 70.00

y = 0.20(1) + 70 → y = 0.20 + 70 → y = 70.20

y = 0.20(2) + 70 → y = 0.40 + 70 → y = 70.40

y = 0.20(3) + 70 → y = 0.60 + 70 → y = 70.40

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2. Answer:

`\begin {array}cx&1&2&3&4\\ y&4.50&6.00&7.50&9.00\\\end{array}`

Explanation:

shoes costs $3.00 - this is a one-time flat fee

it costs $1.50 per game of bowling - this is the unit rate

y = 1.50x + 3.00

y = 1.50(1) + 3.00 → y = 1.50 + 3.00 → y = 4.50

y = 1.50(2) + 3.00 → y = 3.00 + 3.00 → y = 6.00

y = 1.50(3) + 3.00 → y = 4.50 + 3.00 → y = 7.50

y = 1.50(4) + 3.00 → y = 6.00 + 3.00 → y = 9.00

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3. Answer: Negative

Explanation:

As the x-values increase, the y-values decrease. Opposite directions results in a negative slope.

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4. Answer: Gym A → y = 20x + 50 Gym B → y = 25x + 30

Explanation:

Use the slope formula:
`m = (y_2-y_1)/(x_2-x_1)`. Then choose ONE of the points and input the point (x₁, y₁) and slope (m) into the Point-Slope formula: y - y₁ = m(x - x₁) and solve for y.

Gym A: (x₁, y₁) = (1, 70) and (x₂, y₂) = (2, 90)

`m=(90-70)/(2-1) = (20)/(1) = 20`

y - 70 = 20(x - 1)

y - 70 = 20x - 20

y = 20x + 50

Gym B: (x₁, y₁) = (1, 55) and (x₂, y₂) = (2, 80)

`m=(80-55)/(2-1) = (25)/(1) = 25`

y - 55 = 25(x - 1)

y - 55 = 25x - 25

y = 25x + 30