a. ( 5 - √7 ) x = 28 -10
x= 18 / ( 5 -√7 ) = [18( 5+√7) ] / ( 5² - √7 ²) = 18[ 5+√7 ]/ 18= 5+√7
b. ( 2x+7) ·2 = 3 [ 2+x+2]
4x+14=3x +12
x= 12-14=-2
c. ( 2x +3 ) ( x+1) = ( 2x +5) ( x+3)
2x² +3x +2x+3 = 2x² +5x+2x+15
5x +3 = 7x +15
5x -7x= 15 -3
-2x= 12 x=-6