2x + x + 4 +2x = x + 20 5x + 4 = x + 20 5x - x = 20 - 4 4x = 16 x = 4
2x + 4y = 16 <=> 2x + 4y - 16 = 0 2x - 4y = 0 2x - 4y = 2x + 4y - 16 -8y = -16 y = 2 Substituting the known value for y in either of the original equations enables x to be determined. 2x + (4*2) = 16 : 2x = 16 - 8 : x2x = 8 : x = 4 2x - (4*2) = 0 : 2x - 8 = 0 : 2x = 8 : x = 4. The ordered pair satisfying both equations is (4,2)
What is X if 2x + 4 = 36 What is X ? 2x + 4 = 36
If X = 4 then 2X = 2 x 4, which is 8
If 3X - 4 ------ = 0 1-2X-4 So 3X - 4 ----- = 0 [ x (2X-3) ] 2X-3 3X-4 = 2X-3 [ -2X ] X - 4 = -3 [ +4 ] X= 1
2x + 4 = 16 2x = 16 - 4 2x = 12 x = 12/2 x = 6
2x+4 = -16 2x = -16-4 2x = -20 x = -10
(2x + 4)(2x - 4) to check your answer, use the FOIL method (first, outside, inside, last) F.... 2x x 2x = 4x^2 0.... 2x x -4 = -8x I..... 2x x 4 = 8x L.... 4 x -4 = -16 so 4x^2 - 16 = (2x + 4)(2x - 4)
2x + 7 + 2x = 23 4x + 7 = 23 4x = 16 x = 16/4 x = 4
x=3
2x + x + 4 +2x = x + 20 5x + 4 = x + 20 5x - x = 20 - 4 4x = 16 x = 4
x= 2 because 2x+4=16 4x2=8 8+2 or 8x2=16
2x + 4y = 16 <=> 2x + 4y - 16 = 0 2x - 4y = 0 2x - 4y = 2x + 4y - 16 -8y = -16 y = 2 Substituting the known value for y in either of the original equations enables x to be determined. 2x + (4*2) = 16 : 2x = 16 - 8 : x2x = 8 : x = 4 2x - (4*2) = 0 : 2x - 8 = 0 : 2x = 8 : x = 4. The ordered pair satisfying both equations is (4,2)
(4 + 2x) - (-2x + 1) = 13 + 6 4 + 2x + 2x -1 = 19 4x +3 = 19 4x = 19 - 3 4x = 16 therefore x = 16/4 x = 4
2X^2 - 32 = 0 2X^2 = 32 X^2 = 16 X = +/- 4 yes, (X-4) would be a factor, as...... x-4 = 0 X = 4 or 2x2 - 32 = 2(x2 - 16) = 2(x - 4)(x + 4)
The value of X in the equation 2x plus 36 = 4 is -16.
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