Answer:
Step-by-step explanation:
-5x-4y=-4 ...(1)
25x+ 20y = 20 ....(2)
multiply (1) by -5 you have : 25x+ 20y = 20 ....(2) same equation , same line
so : The system has infinitely solutions.
A hamburger costs $2.5 and a milkshake costs $1.75
Step-by-step explanation:
- Step 1: Form equations from the given details. Let cost of 1 hamburger be H and cost of 1 milkshake be M.
4H + 2M = 13.50 ------ (1)
& 3H + 1M = 9.25 ------ (2)
- Step 2: Multiply eq(2) with 2 to make coefficients of M equal.
6H + 2M = 18.50 ------- (3)
- Step 3: Subtract eq(3) from eq(1)
⇒ - 2H = - 5
⇒ H = $2.5
- Step 4: Substitute value of H in eq(2) to find M.
⇒ 3 × 2.5 + M = 9.25
⇒ 7.5 + M = 9.25
⇒ M = $1.75
Answer:
a) -3 gallons per hour
b) y = -3x +14
Step-by-step explanation:
Rate of change is computed by dividing the amount of change by the interval over which it occurred.
<h3>a)</h3>
Here the amount of gas decreased from 14 to 2 gallons, so a decrease of 14-2 = 12 gallons. That occurred over a 4-hour period, so the rate of change is (-12 gallons)/(4 hours) = -3 gallons/hour.
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<h3>b)</h3>
The initial amount was 14 gallons, so the equation for the line describing remaining gas will be ...
y = -3x +14 . . . . gas in the tank after x hours