Alexis received an 85 89 and 92 and three test how many points does she need to score on your next test in order to have an average of at least 90

Lets say Alexis received 85, 89, 92, and x points in her four tests.

Average of a data set or the mean of a data set, we need to add all the values together and divide by the number of values in the set.

So here 85, 89, 92, and x are the values of the data set and the number of values are 4 (since there are 4 tests).

where 'n' represents the number of values and sum represents the total sum of the values.

Here we need to know how much Alexis need to score in her next test so that she can have an average of 90.

So we know the value of average that is 90.

Now,

Solving for 'x' we get:

Therefore,

So, Alexis need to score at least 94 on her next test in order to have an average of at least 90.

c

step-by-step explanation:

region b will make the inequalities y < 2x + 1 and y > -x - 2 true ⇒ answer a

step-by-step explanation:

* lets study the graph and the inequality to solve the question

- the inequality y > -x - 2

∵ the form of the inequality is y > mx + c , m is the slope of the line

  and c is the y-intercept (the line intersect y-axis at point (0 , c)

∴ c = -2 that means the line intersect the y-axis at point (0 , -2)

∵ the sign of the inequality is >

∴ we shad the part over the line

  region a and b

- the inequality y < 2x + 1

∵ the form of the inequality is y > mx + c , m is the slope of the line

  and c is the y-intercept (the line intersect y-axis at point (0 , c)

∴ c = 1 that means the line intersect the y-axis at point (0 , 1)

∵ the sign of the inequality is <

∴ we shad the part under the line

  region b and c

∵ the common region between the two lines is region b

∴ region b will make the inequalities y < 2x + 1 and y > -x - 2 true