Which of the following equations have exactly one solution? Choose all answers that apply:

A
2x-31=2x-312x−31=2x−312, x, minus, 31, equals, 2, x, minus, 31

B
2x-31=-2x-312x−31=−2x−312, x, minus, 31, equals, minus, 2, x, minus, 31

(Choice C)
2x+31=2x-312x+31=2x−312, x, plus, 31, equals, 2, x, minus, 31

(Choice D)
2x-2=2x-312x−2=2x−31

step-by-step explanation:

1. practice, practice & more practice

2. review errors

3. master the key concepts

do not try to memorise the processes.

4. understand your doubts.

5. create a distraction free study environment

6. create a mathematical dictionary

7. apply maths to real world problems.

(sin 42)/31. = sinx)/37

sinx = 37 (sin42)/31

= 37× 0.66/31 = 0.787

x= 51.9

other angle opposite to y = 180-51.9-42

= 180- 93.9 =86.1

so

sin42)/31 = sin 86.1)/y

0.021 = 0.997 /y

y= 0.997/0.021 =47.47