Let x be the mass of the paperbacks and y be the mass of the textbook.
20x + 9y = 44.4 ----------- (1)
25x + 10y = 51 -------------(2)
(1) x 10:
200x + 90y = 444 --------(1a)
(2) x 9:
225x + 90y = 459 --------(2a)
(2a) - (1a):
25x = 15
x = 0.6 -------- sub into (1)
20 (0.6) + 9y = 44.4
12 + 9y = 44.4
9y = 44.4 - 12
9y = 32.4
y = 3.6
So the paperback's mass is 0.6 pounds and textbook is 3.6 pounds
<u>Answer:</u>
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<u>Step-by-step explanation:</u>
From the graph, we can see that y = -1 when x = 0.
So to check whether which of the given options is the equation of the given graph, we will set our calculator to the radian mode and then plug the value of x as 0.
1. y = cos(x + pi/2) = cos(0 + pi/2) = 0
2. y = cos(x+2pi) = cos(0+2pi) = 1
3. y = cos(x+pi/3) = cos(0+pi/3) = 1/2 = 0.5
4. y = cos(x+pi) = cos(0+pi) = -1
Therefore, the equation of this graph is y = cos(x+pi) = cos(0+pi) = -1.
We can easily work out the meter reading in October. It comes out to be 32347 + 972. So the reading in October must be around 33319.
SO the answer to second question is really easy to figure out too. As we know that one unit costs 14 p we can simply multiply the cost with the number of units consumed.
So for 972 units if we multiply by 14 we get the cost to be around somewhere 13608 p.
To find the equation of this line in slope-intercept form (y = mx + b, where m is its slope and b is its y-intercept), we naturally need the slope and the y-intercept. We can see that the line intersects the y-axis at the point (0, 4) so our y-intercept is 4, and the line rises 4 along the y-axis for every 2 it runs along the x-axis, so its slope is 4/2 = 2. With this in mind, we can write the line's equation as
y = 2x + 4
9m+14=2m
9m-2m= -14
7m = -14
m= -2
to check: u need to chance the m to -2
9m - 2m= -14
9 × -2= -18
-2 × -2= -4
-18 - (-4)= -14
i think is right
