Answer:
x=5
Step-by-step explanation:
4x + 8 = 28,
it's rather straight forward,
you would subtract 8 from the left side,
doing the same on the right.
now you have
4x = 20
x= 20/4
x=5
hope this helps.
Answer:
Here are my hints. You can solve it yourself
1/ xy = -12 --> x = -12/y
2/ (-12/y) + y = -1 --> -(12/y) + (y²/y) = -1 --> -12 + y² = -y --> y²+y-12=0
3/ From y²+y-12=0 we can find y then use y to find x and then do your
(x+3) * (y+3)
Answer:
x=37
Step-by-step explanation:
angles inside a triangle add up to 180
add all angles equal to 180
(x+10)+(3x-5)+(x)=180
remove parenthesis, combine like terms
5x-5=180
add 5 both sides
5x=185
divide by 5
x=37
angles: 37, 47, 106
Answer:
a)
b)
c)
Step-by-step explanation:
Part a
The confidence interval for the mean is given by the following formula:
(1)
The Confidence is 0.98 or 98%, the value of
and
, and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.01,0,1)".And we see that
Now we have everything in order to replace into formula (1):
Part b
Part c
The margin of error is given by this formula:
(a)
And on this case we have that ME =0.4/2 =0.2 we are interested in order to find the value of n, if we solve n from equation (a) we got:
(b)
The critical value for 95% of confidence interval now can be founded using the normal distribution. And in excel we can use this formla to find it:"=-NORM.INV(0.025;0;1)", and we got
, replacing into formula (b) we got: