Answer:
or
Step-by-step explanation:
-7,-3,1,5,... is a arithmetic sequence.
Arithmetic sequences have a common difference. That is, it is going up by 4 each time.
When you see arithmetic sequence, you should think linear equation.
The point-slope form of a line is 
.
m is the common difference, the slope.
Any they are using the point at x=1 in the point slope form. So they are using (1,-7).
So let's put this into our point-slope form:
Subtract 7 on both sides:
So your answer is
Answer:
she didnt multiply 5 times 12
Answer:
195 mL of the 90% solution
Step-by-step explanation:
Let the number of mL of 90% mixture = x
Hence, our equation is
780mL × 15% + x mL × 90% = (780mL + x) 30%
117 + 0.9x = 234 + 0.3x
Collect like terms
0.9x - 0.3x = 234 - 117
0.6x = 117
x = 117/0.6
x = 195 mL
Therefore, You will need 195 mL of the 90% solution
The value of the interior angle of the regular polygon is calculated using the formula (n - 2) 180 / n where n is the number of sides of the regular polygon.
<u>Step-by-step explanation:</u>
A regular polygon refers to a multi-sided convex figure where all the sides are equal in length and all the angles have equal degree measures.
The triangle has 3 interior angles of 60 degrees
The square has 4 interior angles of 90 degrees.
The pentagon has 5 interior angles of 108 degrees .
The formula for the interior angle of a regular polygon is given by,
(
n
−
2
)
180 / n
where n refers to the number of sides.
Triangle : (3 - 2) 180 / 3 = 60 degree.
Square : (4 - 2) 180 / 4 = 90 degree.
Pentagon: (5 - 2) 180 / 5 = 108 degree.
