M + 3n =7 help me solve m

What is not true about kl and mn? what is mn? (show )

If a company produces x units of an item at a cost of $35 apiece the function c=35x is a of the total production costs

The value, v, of kalani’s stock investments over a time period, x, can be determined using the equation v=750(0.80)^-x. what is the rate of increase or decrease associated with this account? 20% decrease 20% increase 25% decrease 25% increase