Prove that √ 2 + √ 6 is irrational. (note that, in general, the sum of two irrational numbers could be rational.)

Which is the equation of an ellipse with directrices at x = ±4 and foci at (2, 0) and (−2, 0)?

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. what distance from city a is the point where the truck and the car will meet?

Aplane intersects a pris paralel to the base of the prism. the cross section is a polygon wth eight sides. how many sides does the base of the prism have? a. 10 b. 8 c. 7 d. 9