Step-by-step explanation:
First, apply the distributive property to the left side of the equation. Multiply each of the two numbers inside the parentheses by 12 and then combine those products. Next, solve as you would solve any two-step equation. To isolate \begin{align*}12x\end{align*} on the left side of the equation, add 24 from both sides.
Answer:
1: D
2: B
3: y=-4x+22
4: y=-8x+26
Step-by-step explanation:
1: Parallel lines have the same slope, and the only one with a slope of 3x is D
2: Perpendicular lines have an opposite slope, so a line with a slope of -1/2 would be 2, so you just flip the number and add or take away a negative sign, depending on the original slope
3: Like I said before, perpendicular lines have an opposite slope, so the slope would be -4. After you've figured that out, you just plug in the numbers given to you (and remember, x is first, y is last)
Plug in: 6=-4(4)+b
You would then solve for b.
6=-16+b
22=b
Then plug that into y=mx+b, with m being the slope (-4) and b being the y intercept (22)
4: The process for finding parallel and perpendicular lines is very similar, except you don't have to change the slope.
Plug in: 10=-8(2)-b
10=-16+b
26=b
Again, plug that into the equation y=mx+b
Hope I could be of help! Sorry if it doesn't make sense, this is my first time on this website.
3x^2+12x+15=0
Then divide by 3 to get the x by itself.
x^2+4x+5=0
Factor to (x+5) (x-1) and solve for the two values of x.
∆PQR and ∆SQT are similar, so corresponding sides occur in fixed ratios with one another. This means
SQ / PQ = ST / PR
Solve for x :
8 / ((x + 5) + 8) = (x - 9) / 21
8 / (x + 13) = (x - 9) / 21
168 = (x - 9) (x + 13)
168 = x² + 4x - 117
x² + 4x - 285 = 0
(x + 19) (x - 15) = 0
⇒ x = -19 or x = 15
But x can't be smaller than 9, otherwise ST = x - 9 would be a negative length. So x = 15.