Help thank you show work

x = 12 degrees.

Step-by-step explanation:

The triangle ABC is a right triangle, which means that it has a right angle of 90 degrees.

This is represented by the small square on the bottom-left corner of the triangle.

The angle DBC is 78 degrees. There is also the angle of ABD, which is represented by X.

The right angle is equivalent to 78 degrees and x. You can represent this in an equation, where the sum of 78 degrees and x = 90 degrees, the right angle:

78 + x = 90

x = 12

$20.01

step-by-step explanation:

the sale price is (1.00 - 0.77)($87), or 0.23($87), or $20.01.

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for