Answer:
B or C
Step-by-step explanation:
Measurement is the assignment of a number to a characteristic of an object or event, which can be compared with other objects or events. ... This system reduces all physical measurements to a mathematical combination of seven base units. The science of measurement is pursued in the field of metrology.
I will solve your system by substitution.<span><span>x=<span><span>3y</span>−1</span></span>;<span><span><span>5x</span>−<span>7y</span></span>=19</span></span>Step: Solve<span>x=<span><span>3y</span>−1</span></span>for x:Step: Substitute<span><span>3y</span>−1</span>forxin<span><span><span><span>5x</span>−<span>7y</span></span>=19</span>:</span><span><span><span>5x</span>−<span>7y</span></span>=19</span><span><span><span>5<span>(<span><span>3y</span>−1</span>)</span></span>−<span>7y</span></span>=19</span><span><span><span>8y</span>−5</span>=19</span>(Simplify both sides of the equation)<span><span><span><span>8y</span>−5</span>+5</span>=<span>19+5</span></span><span>(Add 5 to both sides)
</span><span><span>8y</span>=24</span><span><span><span>8y</span>8</span>=<span>248</span></span>(Divide both sides by 8)<span>y=3</span>Step: Substitute3foryin<span><span>x=<span><span>3y</span>−1</span></span>:</span><span>x=<span><span>3y</span>−1</span></span><span>x=<span><span><span>(3)</span><span>(3)</span></span>−1</span></span><span>x=8</span><span>(Simplify both sides of the equation)</span><span>
x=<span><span>8<span> and </span></span>y</span></span>=3
Time used for the call to Zurich: ($5-$1.25)/$0.25=15 minutes
15minutes+3minutes=18minutes
Time used for the call to London: ($7.25-$1.25)/$0.25=24 minutes
24minutes+3minutes=27minutes
Difference between the two calls:27-18=9minutes
Answer:
Step-by-step explanation:
Use the midpoint formula: 
So, the Change In X is 2-8 = -6
And the Change in Y is 7-4 = 3
Once you divide both of the changes by 2, you get
X: -3
Y: 
So the midpoint is: 
