Simplify the following expression.
x4 + 3x2 - 2x* -5x2 - x + x2 + x +1+7x4

Aline has a slope of 1/4 and passes through point (0.4,-1/2). what is the value of the y-intercept?

Can someone me with this problem i don't understand i need

Two cyclists 84 miles apart start riding toward each other at the samen time. one cycles 2 times as fast as the other. if they meet 4 hours later what is the speed (in miles) of the faster cyclists