Answer:
Step-by-step explanation:
t1 means a1 and t7 means a7
a+(n-1)d=an
a+(1-1)d=4
so we get a as 4
<u><em>a=4</em></u>
4+(7-1)d=22
4+6d=22
6d=22-4
d=18/6
<u><em>d=3</em></u>
