Factor b^4 - 2b^2 - 63

What two criteria are needed for triangles to be similar

Pls never taught i’m really confused and i rlly need

At the beginning of the year, adrian's savings account balance was \$28$28. each week, he deposits another \$15$15 into that account, and he doesn't spend any of his savings. is his savings account balance proportional to the number of weeks since the start of the year?