Answer:
It's A, c =2.5d
Step-by-step explanation:
When it comes to problems like this, I usually look through the answers and try to plug in the numbers until I get the right equation that fits with the graph.
2.5(5) = 12.5
2.5(10)= 25
2.5(15)= 37.5
2.5(20) = 50
2.5(25) = 62.5
If you compare this to the graph, you'll notice the solutions are the same as the Total Cost (c). That's because c= 2.5d is the right equation for this graph. (Sorry if my explanation is confusing)
Answer:
<em>The washing machine cost $600 before tax</em>
Step-by-step explanation:
<u>Percentages
</u>
The washing machine cost $651 including a tax of 8.5%.
If x was the cost of the washing machine before tax, then the tax was:
x*8.5/100 = 0.085x
It was added to the original price:
x + 0.085x = 1.085x
That is the final price, thus
1.085x=$651
Solving:
x = $651/1.085
x = $600
The washing machine cost $600 before tax
9/4x -15 for x=4
To find this answer you must plug the 4 everywhere the x is located.
(9/4)(4) -15
Multiply 9/4 by 4
(9/4) x 4 = 9
Now we take our 9 answer and add it to -15.
9-15 = -6
The answer is -6
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-
For the other equation, you also must plug in 3 where ever x is located in the equation.
5/3x -3/5
(5/3)(3) -3/5
Multiply 5/3 and 3
(5/3) x 3 = 5
Take that answer of 5 and add -3/5
5- (3/5) =4 2/5
The answer to this equation would be 4 2/5 or 4.4
Y = mx + b
slope(m) = -1
(2,-4)...x = 2 and y = -4
now we sub and find b, the y int
-4 = -1(2) + b
-4 = -2 + b
-4 + 2 = b
-2 = b
y = -x - 2
x + y = -2 <== standard form
