Can anyone answer these questions

see explanation

see explanationStep-by-step explanation:

21

Note that

(a - )²

= a² - 2 +

= a² + - 2

= 11 - 2

= 9

Thus

(a - )² = 9 ( take the square root of both sides )

a - = 3

22

Since the expression is a perfect square, then

(4x + 5y)²

= 16x² + 40xy + 25y²

Comparing coefficients, then

a - 1 = 40 ( add 1 to both sides )

a = 41

23

99² - 87² ← is a difference of squares and factors as

= (99 - 87)(99 + 87)

= 12 × 186 = 1152, thus

24a = 1152 ( divide both sides by 24 )

a = 48

answer: a video game has three difficulty levels: easy, medium, and expert. the game's scoring works in such a way that a player has to score a fixed number of points to advance to the next level, and then the scoring starts over. the total score needed to clear all three difficulty levels is 7,500. two times the number of points needed to clear the easy level is 500 more than the number of points needed to clear the medium level. twice the number of points needed to clear the medium difficulty level is 1,500 more than the number of points needed to clear the expert level. if x, y, and z represent the easy, medium, and expert levels, respectively, and a is the coefficient matrix of the system of equations modeling this situation, identify the inverse matrix, a-1, and the solution matrix, x, of the system of equations.

ask for details followreport by buttfacelily 2 minutes ago

answers

rauschg

rauschg · hand

know the answer? add it here!

step-by-step explanation: