Answer:
m∠C = 122°
Step-by-step explanation:
Opposite angles of a quadrilateral inscribed in a circle are supplementary. This means
m∠A + m∠C = 180°
m∠B + m∠D = 180°
To find angle C we need to find x, then subtract m∠A from 180°
x+20=3x
20=2x
x=10
Now we substitute 10 in for x
m∠A=2(10)+38
m∠A=20+38
m∠A=58°
Now we subtract this value from 180.
m∠C=180-58
m∠C=122°
Robbie bought the smallest amount. Let's use x for that amount.
Let's use n for amount that each following customer increases.
We have:
Robbie=x
Cameron=x+n
Louis=x+n+n
Tom=x+n+n+n
Charlie=x+n+n+n+n
We know that they bought total of 60 scones.
Robbie + Cameron + Louis + Tom + Charlie = 60
x + x+n + x+n+n + x+n+n+n + x+n+n+n+n = 60
5x + 10n = 60 /:5
x + 2n = 12
We are also given this information:
(Robbie + Cameron) = 3/7 * (Louis + Tom + Charlie)
We insert the equations from above:
(x + x+n) = 3/7 * (x+n+n + x+n+n+n + x+n+n+n+n)
2x + n = 3/7 * (3x + 9n) /*7
14x + 7n = 3* (3x + 9n)
14x +7n = 9x + 27n
We take everything on the left side.
14x + 7n - 9x - 27n = 0
5x - 20n = 0/:5
x - 4n = 0
Now we have two equations:
x + 2n = 12
x - 4n = 0
We solve second one for x and insert it into first one.
x + 2n = 12
x = 4n
4n + 2n =12
6n = 12 /:6
n = 2
x=4*2
x=8
Now we can solve for the amount for each customer.
Robbie=x = 8
Cameron=x+n = 8 + 2 = 10
Louis=x+n+n = 8 + 2 + 2 = 12
Tom=x+n+n+n = 8 + 2 + 2 + 2 = 14
Charlie=x+n+n+n+n = 8 + 2 + 2 + 2 + 2 = 16
Hello! I can help you! First things first, because they are both the same angles on opposite sides, let's set this up in the form of an equation and solve for "x". It would be set up like this:
2x + 20 = 3x - 30
You see up top that it says 2(x + 10). What you would do is multiply what's in the parenthesis by 2, in order to get 2x + 20. Then put the equal sign and write 3x - 30. Subtract 3x from both sides to get -1x + 20 = -30. Subtract 20 from both sides to get -1x = -50. Divide each side by -1 to isolate the "x". In this case, because you are dividing a negative number by a negative number, your quotient will be positive. -50/-1 is 50. Let's plug in the value as "x" and see if it works. 50 * 2 is 100. 100 + 20 is 120. 50 * 3 is 150. 150 - 30 is 120. 120 = 120. There. x = 50.
Answer:
D
Step-by-step explanation: