The sum of the interior angles of a triangle is always 180 degrees. Thus,
the sum of 31, x+4 and 3x+9 must be 180.
31 + x + 4 + 3x + 9 = 180, or 44 + 4x = 180
While it's not necessary, y ou could reduce this equation before solving for x:
11 + x = 45. Then x = 34 degrees.
The three angles are then:
31
34+4 = 38
3(34) + 9 = 111
Check: show that 31+38+111 = 180 (degrees)
x = 3 ; y = 1
Given:
y = -2x + 7
y = 1/3x
Substitute y by its value to find x.
y = y
1/3 x = -2x + 7
x = (-2x + 7) ÷ 1/3
x = (-2x + 7) * 3/1
x = -6x + 21
x + 6x = 21
7x = 21
7x/7 = 21/7
x = 3
Substitute x by its value to solve for y.
y = -2x + 7
y = -2(3) + 7
y = -6 + 7
y = 1
y = 1/3 x
y = 1/3 * 3
y = (1*3)/3
y = 3/3
y = 1
Answer:
wat
Step-by-step explanation:
Answer:
-5
Step-by-step explanation:
The parabolas equation is
(y - k)^2 = 4p(x - h)
Where h,k is the vertex
Substituting the vertex ad (2,-4)
(y - -4)^2 = 4p(x - 2)
(y +4)^2 = 4p(x - 2)
We need to find p from the other point they give us (-3,-3)
(-3 +4)^2 = 4p(-3 - 2)
1^2 = 4p (-5)
1 = -20p
Divide by -20
1/-20 = -20p/-20
-1/20 = p
Substituting back into the equation
(y +4)^2 = 4(-1/20)(x - 2)
Simplifying
(y +4)^2 = (-1/5)(x - 2)
FOILing
y^2 +8y +16 = -1/5x +2/5
Multiply by 5
5y^2 +40y +80 = -x +2
Subtract 2
5y^2 +40y +80-2 = -x +2-2
5y^2 +40y +78 = -x
Multiply by -1
-5y^2 -40y -78 = x
The coefficient of y^2 is -5
Answer:
The 96% confidence interval for the population proportion of customers satisfied with their new computer is (0.77, 0.83).
Step-by-step explanation:
We have to calculate a 96% confidence interval for the proportion.
We consider the sample size to be the customers that responded the survey (n=800), as we can not assume the answer for the ones that did not answer.
The sample proportion is p=0.8.
The standard error of the proportion is:
The critical z-value for a 96% confidence interval is z=2.054.
The margin of error (MOE) can be calculated as:
Then, the lower and upper bounds of the confidence interval are:
The 96% confidence interval for the population proportion is (0.77, 0.83).
