Answer:
Her speed on the summit was 35 mph.
Step-by-step explanation:
Her speed on the summit was "x" mph while her speed while climbing was "x - 10" mph. The distance she rode uphill was 55 miles and on the summit it was 28 miles. The total time she explored the mountain was 3 hours. Therefore:
time uphill = distance uphill / speed uphill = 55 / (x - 10)
time summit = distance summit / speed summit = 28 / x
total time = time uphill + time summit
3 = [55 / (x - 10)] + 28 / x
3 = [55*x + 28*(x - 10)]/[x*(x - 10)]
3*x*(x - 10) = 55*x + 28*x - 280
3x² - 30*x = 83*x - 280
3x² - 113*x + 280 = 0
x1 = {-(-113) + sqrt[(-113)² - 4*(3)*(280)]}/(2*3) = 35 mph
x2 = {-(-113) - sqrt[(-113)² - 4*(3)*(280)]}/(2*3) = 2.67 mph
Since her speed on the uphill couldn't be negative the speed on the summit can only be 35 mph.
Answer:
negative
Step-by-step explanation:
looking at the slope of the straight line, a positive slope will begin on the 1st quadrant and end at the 3rd quadrant
meaning if the slope is negative, it will begin on the 2nd quadrant and end on the 4th quadrant
Answer:
$25.80
Step-by-step explanation:
40% = 40/ 100 = 4/10 = 0,4
There is a 40% discount, which means that the amount multiplied by more then 1 (for example 1,4) would increase the amount... That isn't right because it is a discount!
So you need to subtract the 40%, so (1 - 0.4 =) 0.6
The amount multiplied by 0.6 will be the correct amount, being $43 * 0.6 = $25.80 (rounded to the nearest cent).
The amount the item actually cost after the discount is $25.80
Answer:
y=4
Step-by-step explanation:
if y+2=6, you can subtract 2 from both sides, giving you y=6-2. 6-2=4, which is y.
First divide 32 by 8
32/8
=4
Then multiply the 4 by 3 to find out how many students in the class like to ride their bicycles to school
4x3
12 students is your answer
