Answer:
Step-by-step explanation:So we know x + y = 21 and 5x +10y = 165 We line them up in columns x + y = 21 5x +10y = 165 To eliminate the x variable, I'll multiply every element in the 1st equation by -5. -5x + -5y = -105 5x + 10y = 165 Now we combine (add) the equations, which eliminates x altogether. 5y = 60 ... y = 12 From there, x + 12 = 21 ... x = 21-12 ... x = 9 You should double check. Do 9 nickles and 12 dimes equal $1.65? A very important thing to remember using this method is to do the same thing to each element in the equation that you change! I hope that helps.
Answer:
45
Step-by-step explanation:
12 % of the marbles are blue, and
18 % of the marbles are green, so
30 % of the marbles are either blue or green.
There are 150 marbles.
30 % × 150 = 0.30 × 150 = 45
The number of blue or green marbles is 45.
Hope you won't be turned off by a correction, but we really need to use the symbol " ^ " to denote exponentiation.
Thus, we have x^2 = 100
Taking the square root of both sides, we get x = plus or minus 10. Verify, please, that both x = -10 and x = +10 satisfy the given equation.
To solve the problem related to mean solar time where it varies continuously as a traveler's longitude changes, scientists divided the earth into 24 time zones (adding other partial zones to it). All the countries in each time zones had to keep the mean standard time assigned to it.
<h3>What is Mean Standard Time?</h3>
This is the time that is measured by synchronizing clocks in different geographical locations within the same time zone to the same time.
See the link below for more about Mean Solar Time:
brainly.com/question/26063957
Here is the answer. I’m not so sure if my answer is correct about which side should it be shaded and whether it’s a dotted or solid line, but I hope you will get some sort of idea .
