Answer:
.
Step-by-step explanation:
We have been given that 4 days I have 140 copies of a book, 9 days I only have 50 left. We are asked to write an equation 
, where c is number of copies still on hand and t days being available.
We have two points on line (4,140) and (9,50). Now, we will use these points to find slope as:
Now, we will use point-slope form of equation 
and substitute and coordinates of point (9,50) as:
Therefore, our required equation would be .
Y=mx+b where m=slope=(dy/dx) and b=y-intercept (value of y when x=0)
You have two points...(1,-2),(3,2) so
m=(y2-y1)/(x2-x1)=(2--2)/(3-1)
m=4/2=2 now that you have the slope...
y=2x+b, you can use either point to solve for the y-intercept, I'll use (3,2)
2=2(3)+b
2=6+b
b=-4 so the line is:
y=2x-4
I got -19/655 and i know for sure this isnt the correct answer.
I won't answer them all for you (don't want to cheat - need to learn something).
But for the first one given:
<span>-2x-9y=-25
-4x-9y=-23
you set up either x or y (which ever one you want to eliminate) so that one of them cancels.
So this one is easy - you just have to multiply an entire row by negative (doesn't matter which one) - so that the y's will be + and -
Since they're both 9 and they're subracting NOW - you can eliminate the y value. Now add/subtract the x's. So it'd be -2 or 2 depending on how you eliminated y. Then add the number outside of the = sign. Now just solve for x. After that plug in whatever you got for x into both of the rows. Then find the y value.
Hopefully this wasn't confusing -- reply if it is and I will try to simplify. I can give you contact if you need help with the rest
Good luck!</span>
Answer:
x=4.77
Angle 3=98.32 degrees
Angle 6= 81.68 degrees
Step-by-step explanation:
(Assuming these are parallel lines), Angle 3 and angle 5 are equal because they are alternate Angles. Therefore we can write the following equation to solves for x:
16x+22=3x+84 (angle 3=angle5)
Which we can now solve:
16x +22 - 22 - 3x=3x-3x+84-22
13x=62
13x/13=62/13
x=4.77 (2dp)
We can then use this x to calculate angle 3:
16(4.77)+22
76.33+22=98.32 degrees
Finally,
Angle 6 and angle 3 are interior angles, so they add up to 180 degrees.
So to find angle 6,we can just subtract angle 3 from 180:
180-98.32=81.68 degrees.
Hope this helped!
