Help!! arithmetic sequences 1).35,_,_,_,19

2)11,_,_,_,-26

3)-34,_,_,-16

4)23,_,_,_,31

5)2,_,_,_,_,57

The doghouse shown has a floor, but no windows. find the total surface area of the doghouse, including the door.

In triangle abc, the length of side ab is 12 cm, the length of side bc is 5 cm, and the length of side ca is 9 cm. find the measure of angle a using the law of cosines.

3× __ -2=15 7 2× __+1=7 5 7× =22 15 5× __+10=2 8 × __+4=20 6 × =10 3 × __+2=8 6 × __+8=8 9 × __+7=20 6