How to get answer by Mimiwhatsup:

Answer:
Step-by-step explanation:
The term numerical expression is made up of two words, numerical meaning numbers, and expression meaning phrase. ... A numerical expression in mathematics can be a combination of numbers, integers combined using mathematical operators such as addition, subtraction, multiplication, or division.
1) cscΘ = - 2
=>
1
------ = - 2
sinΘ
=> sinΘ = - 0.5 => Θ is in the third and fourth quadrant
=> Θ = 180° + 30° = 210°
and Θ = 360° + 30° = 330°
2) tan Θ = √3
=> Θ = 60° and Θ = 180° + 60° = 240°
Solve for y in 3x+7=y
y=7−3x
Substitute y=7−3x
y=7−3x into 8x−3y=30
8x−3y=30.
17x−21=30
Solve for x
x in 17x−21=30
17x−21=30.
X=3
Substitute x=3 into y=7−3x
y=-2
Therefore,
x=3
y=−2