Answer:
8
Step-by-step explanation:
The equation is of the form
y = kx ← k is the constant of proportionality
To find k use the slope formula
k = ( y₂ - y₁ ) / ( x₂ - x₁ )
with (x₁, y₁ ) = (0, 0) and (x₂, y₂ ) = (2, 16) ← 2 points on the line
k = 
= 
= 8
In standard form, slope is always the negative of the x coefficient over the y coefficient.
If you dont want to have that memorized, you can use algebra to get the equation of the line into slope-intercept form (y=mx+b)
Set it equal to y
2x - 5y = 6
2x = 5y + 6
2x - 6 = 5y
(2/5)x - 6/5 = y
Now it is in slope intercept form. In slope intercept form, the coefficient multiplying with x is the slope of the line. Therefore, the slope equals 2/5.
<u>Answer</u>
c. buying it at a 10 percent discount without sales tax.
<u>Explanation</u>
We are going to compare the 3 choices and then determine the most cost effective.
<em>a. using a paid membership card to buy it at a 10 percent discount.</em>
10% of $100 = 10/100×100 = $10
cost = $100 - $10 = $90
On top of this $90 there is the charges of the membership card.
<em> b. buying it online at a 10 percent discount with a $5 shipping charge.</em>
100%-10% = 90%
90% of 100 = $90
Cost: $90 + $5 = $95
<em>c. buying it at a 10 percent discount without sales tax.</em>
100% - 10% = 90%
90/100 × 100 = $90. This is the must cost effective method since there is no other cost involved.
1.6 !!!!!!!!!! x=1.6 !!!!!
