The range of all real numbers x such that 2x − 5 < 7 and 4x + 10 > 6 is
a. (-1,6)
b. (-infinity, infinity)
c. an empty set
d. (6,-1)
there's two answers. i need both. will give brainliest

m∠a is 90°

m∠b is 40°

second option

step-by-step explanation:

the measures of a triangle equal 180. use that to find x.

2x+3x+4x=180

9x=180

9x/9=180/9

x=20

now you know x, you know angle a is 40°, angle b is 60°, angle c is 80°.

because angle a is 40°, the first option doesn't work.

because angle b is 60°, the second option does work.

when you add angle a and b, you get 100°. complementary means it equals 90°, so the third option doesn't work.

when you add angle a and c, you get 120°, which is not 100.