Answer:
Step-by-step explanation:
To round 4.9 to nearest tenth means to round the numbers so you only have one digit in the fractional part. 4.9 already has only one digit in the fractional part. Thus, 4.9 is already rounded as much as possible to the nearest tenth and the answer is: 4.9
Answer:
If you consume less energy you pay less with respect to the amount of energy you saved. If you saved 16% of total energy you should expect to lower your bill by 16%. Count how much is left -> 1900-1900*0.16=1596$
Look at the picture.
We have the equation (1) 12x + 4y = 40.
We know, the sum of the acute angles in a right triangle is 90°.
Therefore we have the equation (2) (12x + 4y) + (17x - y) = 90
Substitute (1) to (2):
40 + 17x - y = 90 <em>subtract 40 from both sides</em>
17x - y = 50 (3)
We have the system of equations:

Substitute the value of x to (3)

Answer: x = 3 and y = 1.