Answer:
Y=4 X= -6 or (-6,4)
Step-by-step explanation:
Okay so
3x+10y=22
-3x-8y=-14
- basically, it's like one big equation. First, subtract 3x from -3x which cancels out and gives us 0
- 10y minus 8y gives us 2y.
- 22 minus 14 gives us 8
3x+10y=22
<u>-3x-8y=-14</u>
0+2y=8
Now that we have this, we can solve for y. in order to do this, we have to divide both sides by 2.
From here we know that y=4 because the 2s cancel out leaving y and 8 divided by 2 is 4.
y= 4
Now we can fill in. You can pick any equation for this but I'm going to chose the first one.
3x+10y=22
we can fill in 4 for y
3x+10(4)=22
3x+40=22
Next we are going to subtract 40 on both sides.
3x+40=22
-40 -40
3x= -18
Next, we're going to divide -18 by 3.
The 3s cancel out leaving us x. -18 divided by 3 is -6.
x= -6
Hope this helped!! :)
ANSWER
Options B, C and D have exactly 2 significant figures.
<u>EXPLANATION</u>
To see whether the numbers have exactly 2 significant figures, round all to 2 significant figures. The ones that remains the same have exactly 2 significant figures.
yards to 2.s.f
gallons to 2.s.f
feet to 2.s.f
litters to 2.s.f\
meters to 2.s.f
2/5 plus 2/5 is five so we can assume if we multiply it by 4 it will be 10! 2/5 times 4 equals 10!!! Hope this helps! :D
Answer:
a. Grand Mean = 2.799
b. Standard Deviation = 0.01387
c. Standard Error = 0.0016
d. The range with a Z score of 3 = (2.75739, 2.84061)
Step-by-step explanation:
a. Grand mean :
Given that
Sum of 80 values = 223.91
Total observation = 80
Grand mean = 223.91/80 = 2.799
b. With the excel command "STDEV[range of cells]", we get the standard deviation as = 0.01387
c. Standard error = Standard deviation / root of n
d. The range with a Z score of 3 :
lower limit = mean - (3 * SD) = 2.799 - (0.04161) = 2.75739
upper limit = mean + (3 * SD) = 2.799 + (0.04161) = 2.84061
