Which equation can pair with x + 2y = 5 to create an inconsistent system?

Which sum or difference identity would you use to verify that cos (180° - ∅) = -cos ∅? a. sin (α -β) = sin α cos β – cos α sin β b. cos (α -β) = cos α cos β – sin α sin β c. cos (α -β) = cos α cos β + sin α sin β d. sin (α + β) = sin α cos β + cos α sin β

Which of these sequences is a geometric sequence a 1,2,4, 7, 11, 16, 22. b. 2.4.8.14.22.38 c.3.6.9. 15.18,21 d. 3,9,27,81,243,729,

Ateacher brought a pack of 17 batteries . each calculator uses 3 batteries . how many calculator can the teacher fill with batteries