Solve as simultaneous equations or substitute for the x or y value, and then get the other x or y value by substituting.
Substitution method:
y + 4x = -24
x = 3y - 45
Substitute the x into the first equation.
y + 4 (3y-45) = -24
Simplify and solve for y
y + 12y - 180 = -24
13y = -24 + 180
13y = 156
y = 12
Substitute y into one of the equations to find the x value.
x = 3(12) - 45
x = -9
(-9,12) is where the lines intersect.
2 over 9 because if you see there are 3 red and 4 blue
Using the Empirical Rule, it is found that 229 batteries have lifetimes between 3.0 hours and 3.4 hours.
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By the Empirical Rule, in a normal variable: 68% of the measures are within 1 standard deviation of the mean, 95% are within 2 and 99.7% are within 3.
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- Mean of 3.2 hours with a standard deviation of 0.2 hours.
3 = 3.2 - 2(0.1)
3.4 = 3.2 + 2(0.1)
- Thus, between 3 and 3.4 hours is <u>within 2 standard deviations of the mean</u>, which is 95%.
- Out of 241 batteries:

229 batteries have lifetimes between 3.0 hours and 3.4 hours.
A similar problem is given at brainly.com/question/24552083
I think it's the communitive property
The formula for the surface area of a cylinder is
, where r stands for the radius of the base of the cylinder, and h stands for the cylinder's height.