Answer:
A) 
B) T = -5 °C
Step-by-step explanation:
A) Let T be the change in temperature of the week. T is determined as the total temperature change (-20°C) divided by the number of weeks that have passed (4 weeks). The expression is:

B) In order to simplify the expression, simply perform the division.

This means that the temperature has dropped by 5 degrees each week.
Answer:
0.5
Step-by-step explanation:
just divide in a calculator
Answer:
(mn+n²)/(m+n)
Step-by-step explanation:
probability of blue marble= n/(n+m)
probability of red marble= m/(n+m)
probability that process stops = Probability of both blue + probability of both red= n/(n+m) × n/(n+m) + m/(n+m)×m/(n+m)
= (n²+m²)/(n+m)²
P(1st marbel is blue)= P(blue and red) + P(blue and blue)
= mn/(n+m) + n²/(n+m)
= (mn+n²)/(m+n)
P(1st marble is blue | process stops)= ( (mn+n²)/(m+n)× (n²+m²)/(n+m)²)/ ((n²+m²)/(n+m)²)
= (mn+n²)/(m+n)
Answer:
Triangle 1: x = 80 degrees, acute
Triangle 2: x = 10 degrees, right
Step-by-step explanation:
Triangle 1:
By the Sum of Interior Angles Theorem, all the angles inside the triangle adds up to 180 degrees. So, set up this equation:

Solve for x:

So, x = 80 degrees
Because all the angles are less than 90 degrees, this is an acute triangle.
Triangle 2:
By the Sum of Interior Angles Theorem, all the angles inside the triangle adds up to 180 degrees. So, set up this equation (with the right angle given):

Solve for x:

So, x = 10 degrees
Because there is an angle measuring 90 degrees, this is a right triangle.