hope that this answers your problem !
To solve this question, we first need to layout the equation
-2 1/2 -(-1 3/4)
Step 1
-2 1/2-(-1 3/4) ... Equation
Step 2
5/2-(-1 3/4) ... Converted to improper fraction
Step 3
5/2-(-7/4) ... converted to improper fraction
Step 4
5/2--7/4 ... Got rid of parenthesis
Step 5
-3/4 ... Subtract
Answer:
-3/4 ... Answer
So the answer for this problem is C, -3/4
45.90*0.05=2.295.
The answer is $2.30 when you round it off.
3) x² - 121 = 0
x² = 121
x' = +√121
x' = 11
_______________
x'' = - √121
x'' = -11
Solution ⇒ S{-11 ; 11 } or (x-11)(x+11)
4) 4x² + 144 = 0
4x² = -144
x² = -144 / 4
x² = -36
x = √-36
No solution ⇒ S = ∅
5) z²+10z+21 = 0
Δ = 10² - 4(1)(21)
Δ = 100 - 84
Δ = 16
x' = (-10+4) / 2 = -6/2 = -3
x'' = (-10-4) / 2 = -14/2 = -7
Solution ⇒ S{ -7 ; -3} or (x+3)(x+7)