Answer:
2340 degrees
Step-by-step explanation:
Each triangle has an angle sum of 180 degrees, therefore the sum of interior angles of 15-gon will be 13×180=2340
13 + 21 = 13- -21
The minus sign and negative cancel each other out.
Answer:
a) (11/7, 9/7)
b) There's no point of intersection
Step-by-step explanation:
a) x - 2y + 1 = 0
2x + 3y - 7 = 0
To find the point of intersection, we need to solve the system of equations and the result will be the point of intersection (x,y)

Now we substitute x in the second equation:

Now we substitute y in our first equation.
.
The point of intersection is (11/7, 9/7)
b) x -2y +11 =0
-x + 2y - 13 =0
We are going to follow the same procedure:


Since this system of equations doesn't have a solution, the system has no point of intersection.
1) The normal room temperature is said to be about 20°C
2) 5 day is equivalent to 120 hr
3) 756 m³/s is equivalent 56000 L/s
4) It would take the snail 5 hours to crawl 75 m
<h3>What is an
equation?</h3>
An equation is an expression that shows the relationship between two or more numbers and variables.
1) The normal room temperature is said to be about 20°C
2) 1 day = 24 hr
5 day = 5 day * 24 hr per day = 120 hr
3) 1 m³ = 1000 L
756 m³/s = 56 m³/s * 1000 L/m³ = 56000 L/s
4) 1 m = 100 cm
75 m = 7500 cm
Time = 7500 / (25 cm/min) = 300 min = 5 hours
Find out more on equation at: brainly.com/question/2972832
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