(2x + 3y = 12) x (-2)
(4x - 3y = 6) x 1
-4x - 6y = -24
4x - 3y = 6
You can cancel out the x values by adding the two equations together.
(-4x + 4x) + (-6y - 3y) = (-24 + 6)
-9y = -18
y = 2
Solve for x now...
4x - 3(2) = 6
4x - 6 = 6
4x = 12
x = 3
Check... (x = 3, y = 2)
2(3) + 3(2) = 12
6 + 6 = 12
12 = 12 <- this works!
4(3) - 3(2) = 6
12 - 6 = 6
6 = 6 <- this works!
Answer:
Step-by-step explanation:
I suggest looking lessons on it online if you don't understand... It's hard to do your work especially if you don't understand it. Or if your online, go to past lessons or something.
Z = (X-Mean)/SD
<span>z1 = (165 - 150)/15 = +1 </span>
<span>z2 = (135 - 150)/15 = - 1 </span>
<span>According to the Empirical Rule 68-95-99.7 </span>
<span>Mean +/- 1SD covers 68% of the values </span>
<span>100% - 68% = 32% </span>
<span>The remaining 32% is equally distributed below z = - 1 and z = +1 </span>
<span>32%/2 = 16%
</span>
<span>Therefore,
</span>
<span>a) Number of men weighing more than 165 pounds = 16% of 1000 = 160 </span>
<span>b) Number of men weighing less than 135 pounds = 16% of 1000 = 160</span>
