A test is worth a total of 150 points and contains 70 questions. Some of the questions are worth 2 points and some are worth 4 points.

x + y = 70

2x + 4x = 150

y = 70 - x

2x + 4( 70 - x) = 150

2x + 280 -4x = 150

280 -2x = 150

2x = 280 -150

2x = 130

x = 65 (2-Point Questions)

x + y = 70

65 + y = 70

y = 70 -65 = 5 (4 Point Questions)

Checking work:

2(65) +4(5) =150

130 + 20 = 150

150 = 150

Check!

Step-by-step explanation:

up

step-by-step explanation:

the orientation of the parabolas can easily be found by analysing the power of x and y and their signs. if x is squared , parabola opens up and also if its coefficient is negative it opens down. if y is squared , the parabola opens right and also if its coefficient is negative it opens left. however in order to do the above analysis our equation must be in standard form .

our parabola is

which is not standard form of any parabola . hence we square on both hand side and convert it into standard form.

hence we see that x is squared and its coefficient is non negative . there for it opens up.

w'x is 0.

hope it