Truck is 30% less than bus
40 divided by 1.3 = 30.77
Car is 75% less than truck
30.77 divided by 1.75. = 17.58 feet
A
given the 2 equations
2x + y = - 2 → (1)
x + y = 5 → (2)
subtract (2) from (1) term by term to eliminate y
(2x - x ) + (y - y ) = (- 2 - 5 )
x + 0 = - 7 ⇒ x = - 7
substitute x = - 7 in either of the 2 equations and solve for y
(2) : - 7 + y = 5 ( add 7 to both sides )
y = 5 + 7 = 12 → A
Hello!
A sample of Bromine-82 begins at 80 mL. We are given that this value will decrease by half of its current amount every 35 hours. First, we'll determine the number of times that 35 goes into 140. This will reveal the number of times we should divide the sample by 2:
140 ÷ 35 = 4
We have now proven that there are 4 periods of 35 hours in 140 hours. This means that we will divide the sample in half a total of 4 times, as follows:
1. 80 ÷ 2 = 40
2. 40 ÷ 2 = 20
3. 20 ÷ 2 = 10
4. 10 ÷ 2 = 5
We have now proven that an 80 mL sample of Bromine-82 will be reduced to only 5 mL after 140 hours. Therefore, the correct answer is 5 mL.
I hope this helps!
Here,
cos(x) = sin(35)
cos(x) = cos(90-55)
cos(x) = cos(55)
x = 55
