What value of x makes the equation below true? (1 point)
7x - 1 = 9

a 10/7
b 8/7
c 2/7
d 16/7

To solve for a variable, you isolate that variable on one side and whatever that variable equals to is on the opposite side of that variable.

In the equation 7x - 1 = 9 we can see on the left-hand side that the x variable is being multiplied by 7 and -1 is being added to it.

Let's reverse whatever is being done to the x variable so that we can see its value.

Let's add 1 to the left-hand side of the equation. If we do that, then the -1 part will go away.

But remember, whatever we do on one side we must also do on the opposite side.

We do this to keep the equation balanced.

7x - 1 + 1 = 9 + 1
7x = 10

Now we have 7x = 10

We are very close seeing the answer. All we need to do is divide both sides by 7.
That way we will reverse the multiplication operation done to the x variable.

7x / 7 = 10 / 7
x = 10/7

So, A 10/7 is the answer.

Part A. In order to know the function, the first step is to plot the points for both cars. In the picture, this is represented by the blue and orange lines for Car 1 and Car 2, respectively. When you connect the dots, it forms a smooth line. Therefore, both functions are linear.

Part B. In this case, you have to find the m and b for the standard form of a linear equation, y=mx + b, wherein m is the slope and b is the y-intercept. But, you can use MS Excel to make a trendline and know the linear equation from it through linear regression. The equation for car 1 is y=-6000x+38000 and that for car 2 is y=-4481.6x+36661.

Part C. In the formulated equations in Part B, we use this to know the value of y by replacing x = 5 years.

Car 1:
y = -6000(5)+38000 = $8,000
Car 2:
y=-4481.6(5)+36661 = $14,253

There is a significant difference, obviously. For Car 1, the value dropped from $20,000 to $8000 in just a year. For Car 2, the value dropped from $23,336.75 to $14,253 in just a year.