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)
Rewrite the inequality without the absolute value
-18 < x - 13 < 18
Add 13 to the whole equation
-18 + 13 < x < 18 + 13
Simplify
<u>-5 < x < 31</u>
Answer:
17.76
Step-by-step explanation:
0.44 x 4 = 1.76
4 x 4 = 16
16+1.76=17.76
When using distributive properties yes.