Answer:
n = 7
n = -3
Step-by-step explanation:
4n+6 = n²-15
4n = n² - 21
n² - 4n - 21 = 0
(n-7)(n+3) = 0
n = 7
n = -3
Answer:
C
Step-by-step explanation:
180-130 = 50
50 + 80 + x = 180
80 + x = 180 -50
80 + x = 130
Answer: x = 20.
Step-by-step explanation:
x and (3x + 10) combine to form a right angle, shown in the diagram by the small square joining the perpendicular lines.
Right angles are 90 degrees, so you can add both angles to get 90:

Answer:
r - 5 = 2c
r = 75
Step-by-step explanation:
To write an equation for the problem, we first need do declare the value of the number of apps cora has.
Let c = Cora's apps
r - 5 = 2c
r - 5 is used to indicate that Rita deleted 5 apps.
2c is used to represent the twice the number of apps Cora has.
Now you said that Cora had 35 apps.
Let's plug that into the equation.
r - 5 = 2c
r - 5 = 2(35)
r - 5 = 70
Now we transpose the -5 to the other side to leave r.
r = 70 + 5
r = 75
So if Cora has 35 apps, then Rita will have 75 apps.
Answer:
x = ±
Step-by-step explanation:
We have been given the quadratic equation;

The first step is to subtract 50 from both sides of the equation;


Multiplying both sides by -1 yields;

The final step is to obtain square roots on both sides;

Therefore, x = ±