Answer:
x² + 4x + 20 = 12x - 5
x² + 4x - 12x + 20 + 5 = 0
x² - 8x + 25 = 0
Δ = √b² - 4ac
= √(-8)² - 4×1×25
= √64-100
= √(-36)
x ∉ R
Answer:
Area Painted = (2*12*15) + (2*20*12)
Step-by-step explanation:
If you imagine a box, you know that the bottom area would be found by multiplying the length by the width. Thus, the only other area you want to find are the sides of the box. I multiplied the length and the height as well as the width and the height. I multiplied that by 3 because there's two sides that are always going to be the same. I recommend you draw a picture before attempting to write an expression,
Hope this helped :)
Answer:
6
Step-by-step explanation:
Take everything to one side and equate it to zero
So: 5x^2 -x -1=0
Next factorise so it’s 5(x^2-1/5)-1=0
So: 5(x-1/5) ^2 -1=0
So complete the square
First of all remove the five by division (x- ((1/5)/2)^2+ (1/5/2)^2 ) -1 =0
So (x- 1/10)^2 +1/5 +1/100 =0
Answer is (x-1/10)^2 -21/100 =0
Take -21/100 to the other side so:
(x-1/10)^2 = 21/100
Square root both sides so
(X-1/10) = square root of 21/100
Take -1/10 to the other side so
X= 1/10 + square root of 21/100
