Part (a)
<h3>Answer: y1 and y3 are perpendicular</h3>
This is because the two slopes 2 and -1/2 multiply to -1. Perpendicular slopes multiply to -1 assuming neither line is vertical or horizontal.
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Part (b)
Graph each line to see where they cross. The three points of intersection are
(0,4)
(2,-2)
(4,2)
The order of the points doesn't matter.
You could also form three systems of equations pairing up the equations, and solving each system. That way you can find the points of intersection. Graphing may be a better and faster route in my opinion. See the diagram below.
Hey! Let's go through this.
If she has 42 dollars and she buys 3 $7 t-shirts, we can use multiplication to see that she spent 21 dollars on t shirts, meaning she has 42-21 dollars left, or 21 dollars left.
If she has 21 dollars left and glasses sell for $6, then the most she can buy (keep in mind we can't buy a fractional part of a pair of sunglasses) at most 3 pairs, because if she bought four, she'd go over her spending limit.
Hope this helps!
<h3>Answer:</h3>
y = 0.1x +1500
<h3>Explanation:</h3>
You need an equation that will give Gary a salary of $1500 even if he makes no sales (x=0). The only possible choice for the second item is then ...
... +1500
You are expected to know that Gary's commission of 10% of sales is computed by multiplying sales (x) by 10%. That is, if Gary sells $100 worth of items, his commission is ...
... 10% × $100 = $10
That is, the multiplier is 0.1.
Gary's salary (y) is then computed as
... y = 0.1x +1500
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<em>Comment on percentages</em>
The % symbol is a shorthand way to write /100. That is, 10% = 10/100, ten hundredths, or 0.10. (You might notice here that "percent" and "hundredths" can be used interchangeably.)
To find the superficial area of a prism you have to do base perimeter * height
So find the perimeter of the right triangle: 9+8+5 = 22 yd
Then find the superficial area 22*12 = 264 yd^2
