Please help me and explain to me how it’s solved. I don’t get it. Thank you.

Given: m∠ adb = m∠cdb ad ≅ dc prove: m∠ bac = m∠bca lol

Tom is the deli manager at a grocery store. he needs to schedule employee to staff the deli department for no more that 260 person-hours per week. tom has one part-time employee who works 20 person-hours per week. each full-time employee works 40 person-hours per week. write and inequality to determine n, the number of full-time employees tom may schedule, so that his employees work on more than 260 person-hours per week. graph the solution set to this inequality.

Using elimination, what is -4x+2y=-12 4x+8y=-24