Answer:
<em><u>x=-6, y=-2</u></em>, (As a point) (-6, -2).....The point form is not necessary unless you want to solve the system (of equations) by graphing.
Step-by-step explanation:
By substitution:
x-y=-4 By adding y on both sides,
x=y-4
Now you can substitute x for the expression (y-4)
Plug the (y-4) as x in the other equation.
So -2x+3y=6 becomes
-2(y-4)+3y=6
Now solve:
-2(y-4)+3y=6 distributes out to be
-2y+8+3y=6 Now combining like terms
y+8=6 Subtract 8 on both sides to isolate the variable
<u><em>y=-2</em></u>
Now plug the value -2 in where the y is in any equation (preferably the easier/less complicated one) and solve for x.
So x-y=-4 becomes
x-(-2)=-4
=x+2=-4
=<u><em>x=-6</em></u>
The answer is B because in total you there are 15 bicycles and tricycles so b +t =15
Bicycles have 2 wheels and tricycles have 3 wheels so 2b + 3t = 45
Answer:
95%.
Step-by-step explanation:
We have been given that the lifetimes of light bulbs of a particular type are normally distributed with a mean of 370 hours and a standard deviation of 7 hours.
We are asked to find the percentage of the bulbs whose lifetimes lie within 2 standard deviations to either side of the mean using empirical rule.
The empirical rule (68-95-99.7) states that approximately 68% of data points lie within 1 standard deviation of mean and 95% of data points lie within two standard deviation of mean. 99.7% of data points lie within three standard deviation of mean.
Therefore, approximately 95% of data points lie within two standard deviation of mean.
60 miles per hour is the speed