Answer:
It’s the third one
Step-by-step explanation:
-1.1x+6.4>-1.3
-1.1x>-1.3-6.4
-1.1x>-7.7 multiplied by -1 gives 1.1x<7.7
Divided by 1.1 you get x<7
<span>1/2(7x-8)+2x =2-(10x+4)
Distribute
(7x-8)/2 + 2x = 2 -10x -4
combine like terms
(7x - 8)/2 + 2x = -10x - 2
Multiply both sides by 2
7x - 8 + 4x = -20x -4
Combine like terms
11x - 8 = -20x - 4
add 8 to both sides
11x = -20x + 4
add 20x to both sides
11x + 20x = 4
combine like terms
31x = 4
divide both sides by 31
x = 4/31 or </span><span>0.129.
Hope this helps :)</span>
You have to find out what 15% of $78 dollars is. If you have to do this in your head and not on a calculator you can find 10%, then cut that number in 1/2 and add it to the answer. So 10% of $78 is 7.8 so $7.80. You can divide 7.80 by 2 and get 3.9 and add that to 7.8 which is 11.70. So 15% of $78 is $11.70.
4.2x - 1.4y = 2.1 |multiply both sides by 10
42x - 14y = 21 |subtract 42x from both sides
-14y = 21 - 42x |change signs
14y = 42x - 21 |divide both sides by 14
y = 3x - 1.5
Answer:
The kinetic energy is 20,000\ J
Step-by-step explanation:
The kinetic energy of a body is defined as:

Where <em>m</em> is the mass of the roller coaster car
<em>s</em> is the speed and <em>k</em> is the kinetic energy
We know that 

Then the kinetic energy of the roller coaster car is:
