Answer:
x = 12
Step-by-step explanation:
x - 5 = 84/x
x² - 5x = 84
x² - 5x - 84 = 0
x = (5 ±√(5² - 4(1)(-84))) / 2
x = (5 ± 19) / 2
x = -7 ignore
x = 12
Answer: she scored 69 points on the second test.
Step-by-step explanation:
Let x represent the number of points that she scored in the first test.
Let y represent the number of points that she scored in the second test.
If her mean score was 75, it means that
(x + y)/2 = 75
x + y = 75 × 2
x + y = 150- - - - - - - - - 1
If she scored 12 points more on the first test than the second test, it means that
x = y + 12
Substituting x = y + 12 into equation 1, it becomes
y + 12 + y = 150
2y + 12 = 150
2y = 150 - 12
2y = 138
y = 138/2
y = 69
Answer:
This is an exponential decay
Because the base of the exponent is 1/4.4 which is less than 1
Step-by-step explanation:
What is exponential growth?
when the base of our exponential is bigger than 1, which means those numbers get bigger.
What is exponential decay?
when the base of our exponential is in between 1 and 0 and those numbers get smaller.
Y=7x-10
Plz mark me Brainly
Plz let me know if I am correct
X = pencils, y = pens
8x + 6y = 8.50
4x + 4y = 5.....multiply by -2
----------------
8x + 6y = 8.50
-8x - 8y = -10 (result of multiplying by -2)
-----------------add
-2y = - 1.50
y = -1.50 / -2
y = 0.75 <=== pens cost 0.75
4x + 4y = 5
4x + 4(0.75) = 5
4x + 3 = 5
4x = 5 - 3
4x = 2
x = 2/4
x = 0.50 <== pencils cost 0.50
