Answer:
Mr.Kim is presently 40 years old, and his daughter is 15 years old.
Step-by-step explanation:
K is Mr Kim's present age
D=his daughter's present age.
K=D+25 ; or Mr.Kim is his daughter's age plus 25 years.
K+10=2(D+10); or in 10 years, Mr Kim will be twice daughters age
Substitute the K from the first equation into the second equation and then solve for variable D.
(D+25)+10 = 2(D+10) Simplify.
D+35 = 2D+20 You must subtract D from both sides.
35 = D+20 Lastly, subtract 20 from both sides.
15 = D or D = 15
Mr Kim's daughter's is 15 years old.
Mr Kim's age is D+25
15+25 = 40 years old.
I am WHITE, and only speak inglish because I am a 7th grader, only speak snipets of spanish, and not fluent. If you could translate, I would be happy to help you with your question.=)
Answer
Find out the percent error in Annie's estimate .
To prove
Formula
As error = approx value - exact value
As given
Annie estimates that the height of a bookcase is 78.25 in.
The actual height is 75.50 in.
approx value = 78.25 in.
actual value = 75.50 in.
error = 78 .25 - 75 .50
= 2.75
put in the formula
Percentage error = 3.64 % (approx)
Therefore the Percentage error be 3.64 % (approx).
In order to solve by elimination, let's multiply the first equation by -2. This way, when we add the equations, the variable y will be canceled out:
Now, adding the equations, we have:
Now, calculating the value of y, we have:
Therefore the solution is (3, 0).