Answer:
B
Step-by-step explanation:
The student's mistake was between Step 1 and Step 2.
Here, on the left side, they added 6x and 2x. The result should be 8x, not 4x.
It should be 8x-15=3x-75, not 4x-15=3x-75.
Answer:
60 degrees
Step-by-step explanation:
All angles of a triangle will add up to equal 180 degrees.
Set up an equation to solve for x:
9x - 3 + 50 + 9x + 7 = 180
Combine like terms
18x + 47 + 7 = 180
18x + 54 = 180
Subtract 54 from both sides
18x = 126
Divide both sides by 18
x = 7
Now plug in 7 for x in the expression for angle A:
9(7) - 3
63 - 3
60
Check work:
60 + 50 + 9(7) + 7 = 180
110 + 63 + 7 = 180
173 + 7 = 180
180 = 180
Correct
Jamie get's $10,000 dollars added onto her annual paycheck after 10 years.
Wei on the other hand, get's $15,000 dollars added onto his annual paycheck after 10 years.
Jamie's total: $35,000
Wei's total: $34,000
So Jamie would have a better pay than Wei for 10 years, but after that Wei will take the lead.
<span>D) 9.0 x 10^10 km
This is more an exercise in handling scientific notation than anything else. Since we have the distance that light travels in 1 second and we want to calculate how far it travels in 5 minutes, we must first calculate how many seconds are in 5 minutes. Simply multiplying 5 by 60 gives us 300 seconds. Now we need to multiply 300 by 3.0x10^8 km. So
300 * 3.0x10^8 = ?
We could first convert 300 into scientific notion, but it's easier to just leave it along and assume that it's 300 x 10^0. So 300 times 3 is 900. And since 0 plus 8 is 8, we have as the answer:
900 x 10^8
But we're not done. The significand has to be greater than or equal to 1 and less than 10. So let's divide 900 by 100 and add 2 to the exponent. So we get
9 x 10^10
Finally, since our data had 2 significant figures, our result should have that as well. So let's add the 2nd digit getting:
9.0 x 10^10
So we know that light travels 9.0x10^10 km in 5 minutes, and that answer matches option "D" from the available choices.</span>
Goal: Try to get the variable by itself!
5n+4=-26
-4= -4
5n=-30
n=-6