25.35 seconds. Add all 4 numbers and divide by 4
Answer:
84
Step-by-step explanation:
Let x = the test
(x + x + ( x - 6))/3=82
((3x - 6)/3) • 3= 82 • 3
3x - 6 + 6 = 246 + 6
<u>3x</u> = <u>252</u>
3 3
x = 84
Step-by-step explanation:
here is fig 15
x=36 (v.o.a are equal)
36+y=180
y=180-36=144
y=z=144 vertically
John brought 20 water melons each water melon cost him 2 dollars. He gave his friend Bob 3/4 of the watermelons. In return bob gave him double the amount of water melons back. How many watermelons does John have now? How much money did he spend on each water melon?
Answer:
-13, -3
15, 2.6
Step-by-step explanation:
x, y are the numbers
x = 5y + 2
x×y = 39
(5y + 2)×y = 39
5y² + 2y - 39 = 0
the solution of a quadratic equation :
y = (-b ± sqrt(b² - 4ac))/2a
a = 5
b = 2
c = -39
y = (-2 ± sqrt(2² - 4×5×-39))/2×5 =
= (-2 ± sqrt(4 + 780))/10 =
= (-2 ± sqrt(784))/10 = (-2 ± 28)/10
y1 = (-2 + 28)/10 = 26/10 = 2.6
y2 = (-2 - 28)/10 = -30/10 = -3
x1 = 5×2.6 + 2 = 13 + 2 = 15
x2 = 5×-3 + 2 = -15 + 2 = -13
