Answer:
infinite number of solutions
Step-by-step explanation:
Work with the second equation. Subtract 8x from both sides.
- 4y + 8x - 8x = -8x - 12 Collect like terms.
-4y = - 8x - 12 Divide by - 4
-4y/-4 = - 8x/-4 - 12/-4
y = 2x + 3
That is exactly the same line as the first given. There is an infinite number of solutions.
The given equation
x/2 = y/3 = z/4
can be broken into three separate equations which I'll call equations (A), (B) and (C)
- x/2 = y/3 ..... equation (A)
- y/3 = z/4 .... equation (B)
- x/2 = z/4 .... equation (C)
We'll start off solving for z in equation (C)
x/2 = z/4
4x = 2z ... cross multiply
2z = 4x
z = 4x/2 ... divide both sides by 2
z = 2x
Now let's solve for y in equation (A)
x/2 = y/3
3x = 2y
2y = 3x
y = 3x/2
y = (3/2)x
y = 1.5x
The results of z = 2x and y = 1.5x both have the right hand sides in terms of x. This will allow us to replace the variables y and z with something in terms of x, which means we'll have some overall expression with x only. The idea is that expression should simplify to 3 if we played our cards right.
We won't be using equation (B) at all.
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The key takeaway from the last section is that
Let's plug those items into the expression (2x-y+5z)/(3y-x) to get the following:
(2x-y+5z)/(3y-x)
(2x-y+5(2x))/(3y-x) ..... plug in z = 2x
(2x-y+10x)/(3y-x)
(12x-y)/(3y-x)
(12x-1.5x)/(3(1.5x)-x) .... plug in y = 1.5x
(12x-1.5x)/(4.5x-x)
(10.5x)/(3.5x)
(10.5)/(3.5)
3
We've shown that plugging z = 2x and y = 1.5x into the expression above simplifies to 3. Therefore, the equation (2x-y+5z)/(3y-x) = 3 is true when x/2 = y/3 = z/4. This concludes the proof.
Given:
40 pages in 1.6 minutes
40 / 1.6 = 25 pages per minute
25 x 5 minutes = 125 pages
40 / 1.6 = x / 5
40*5 = 1.6x
200 = 1.6x
200/1.6 = x
125 = x pages
25 : 1 = 150 : x
25x = 150
x = 150/25
x = 6 minutes
Answer:
4
Explanation:
The amplitude of a sine function is the absolute value of the coefficient of sin(in other words, the absolute value of the number multiplying the sin)
In this case, that is |-4|=4