Answer:
x = (-19)/3
Step-by-step explanation:
Solve for x:
10 - 2 x + 5 (x + 4) + 3 (2 x + 9) = 0
5 (x + 4) = 5 x + 20:
10 - 2 x + 5 x + 20 + 3 (2 x + 9) = 0
3 (2 x + 9) = 6 x + 27:
6 x + 27 + 5 x - 2 x + 10 + 20 = 0
Grouping like terms, 6 x + 5 x - 2 x + 10 + 20 + 27 = (-2 x + 5 x + 6 x) + (10 + 20 + 27):
(-2 x + 5 x + 6 x) + (10 + 20 + 27) = 0
-2 x + 5 x + 6 x = 9 x:
9 x + (10 + 20 + 27) = 0
10 + 20 + 27 = 57:
9 x + 57 = 0
Subtract 57 from both sides:
9 x + (57 - 57) = -57
57 - 57 = 0:
9 x = -57
Divide both sides of 9 x = -57 by 9:
(9 x)/9 = (-57)/9
9/9 = 1:
x = (-57)/9
The gcd of 57 and 9 is 3, so (-57)/9 = (-(3×19))/(3×3) = 3/3×(-19)/3 = (-19)/3:
Answer: x = (-19)/3
Answer: 7 1/16 and 1 9/16
Step-by-step explanation: 1 3/8 x 1.5 is 1 3/8 x 1 5/10 11/8 x 15/10 which is 165/80. We divide it by 5/5 to get 33/16. This as a mixed number is 2 1/16. We add 5 to get 7 1/16.
5/8 divided by 0.4 is 5/8 divided by 2/5. We divide this by first finding the reciprocal of 2/5 which is 5/2. 5/8 x 5/2 = 25/16. This as a mixed number is 1 9/16.
Answer:
First part = 2.
Time to land = 6 seconds.
Step-by-step explanation:
The object is at h = 0 when it land so
-5x^2 + 20x + 60 = 0
-5(x^2 - 4x) = -60
-5[(x - 2)^2 - 4] = -60
(x - 2)^2 - 4 = -60/-5 = 12
(x - 2)^2 = 16.
Solving the above:
Take the square root of both sides:
x - 2 = 4
x = 2 + 4
x = 6 seconds