If you like riverdale shut up

What is the rule for reflection across the y axis

If x-1 and x+3 are the factors of x3+10x2+ax+b find a and b

Abari owns 100 shares of stock a and 45 shares of stock b. for the past month, his stocks have been fluctuating inversely. stock a decreased by m cents per share and stock b increased by n cents per share. which equation can be used to find the total change in value of jabari's shares per month?