Answer:
x = 45
Step-by-step explanation:
→ Add all the angles together
x + 2x + 3x + 90 = 360
→ Simplify
6x + 90 = 360
→ Minus 90 from both
6x = 270
→ Divide by 6
x = 45
Answer:
2 should be distributed as 2y + 8; y = 4
Step-by-step explanation:
2(y + 4) = 4y
Distribute
2y + 8 = 4y
Step 2 is incorrect because the added instead of multiplied
Continuing on to correct the problem
Subtract 2y from each side
2y+8-2y = 4y-2y
8 = 2y
Divide by 2
8/2 = 2y/2
4 =y
Essentially when people ask you find the solution to system of equation, there asking at what x value do these to graphs intersect. The easiest way to do this is to get a graphing calculator, or desmos and type in the equation and find where they intersect. Heck, even the question says to solve it with a graph, but I'll demonstrate it algebraically.
One way you can do this is set the equation equal to each other. This is because you want to know at what x-value has the same y-value. So we get:
x^2 + 6x + 8 = x + 4
We can then combine like terms, or move everything to one side. So we get:
x^2 + 5x + 4 = 0.
Then we can use the quadratic formula to solve for x.
x=(-5 +/- sqrt(5^2 - 4(1)(4)))/(2(1)
This simplifies into:
(-5 +/- 3)/2
Finally we add and subtract:
(-5 + 3)/2 = x = -1
(-5 - 3)/2 = x = -4
And our solution is x = -1, x = -4
Answer:
C. c = -4
Step-by-step explanation:
you must get c by itself. you have to divide both sides by 10. this gets rid of the 10c and keeps both sides equal
-40/10 = c
c = -4