B is the midpoint of ac. Ab = x+9 and bc = 3x-7 find x and ac
1 answer:
To solve this problem, we need to know 2 relationships:
<h2>1. AC = AB + BC</h2>The distance of AC is the sum of AB and BC.
We know this since the distance of going from A to C (AC) is the same as going from A to B (AB), then B to C (BC).
<h2>2. AB = BC</h2>The distance of AB is the same as AC.
We know this since B is in the middle of AC, so the distance from B to A (BA) is the same as the distance from B to C (BC).
You can see the attached image (at the bottom) for a visualization of this.
<h2>Putting them together</h2>Since we know the values of AB and BC...
...we can put these values into our 2nd equation and solve for x:
Add 7 to both sides:
Subtract x from both sides:
Divide both sides by 2:
Knowing x, we can find the distance of AC using our first equation.
Let's put in the values of AB and BC:
Before we put in x = 8, we can simplify this:
We group x and 3x and add those together. Then we subtract 7 from 9.
With this equation, we can put in x = 8:
Since 4 * 8 = 32:
Finally, we have found both x and AC.
<h2>Answer</h2>x = 8
AC = 34
You might be interested in
9514 1404 393
Answer:
3x -y -30 = 0
Step-by-step explanation:
The reference line for the intercept can be written in standard form as ...
2x +5y = 20
Setting y=0 and solving for x, we find the x-intercept to be ...
2x = 20
x = 20/2 = 10
__
The line perpendicular to the first reference line can use the same x- and y-coordinates, but swapped, with one of them negated. If the line is right-shifted from the origin to the x-intercept point, its equation will be ...
3(x -10) -y = 0
In general form, this is ...
3x -y -30 = 0
_____
<em>Additional comments</em>
Perpendicular lines have slopes that are opposite reciprocals of each other. The slope of a line in general form is ...
m = -(coefficient of x)/(coefficient of y)
The opposite reciprocal of this can be had by swapping the coefficients and negating one of them.
In general form, we like to have the first coefficient positive, so we choose to negate the (new) y-coefficient in this problem.
The general form equation ax+by=0 would define a line through the origin. Using the usual methods for translating functions, we can make the line go through point (h, k) by writing the equation as a(x-h)+b(y-k) = 0. This is the method we used to make the line have the desired x-intercept.
