10x (7x² +9x +6 )
multiply
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10x (7x²) + 10x (9x) +10x (6)
70x³ + 90x² + 60x
simplification
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10x (7x² +9x + 6)
10x(7x² + 9x +6)
7x² + 9x + 6 is a quadratic equation ,
in the form of ax² + bx + c
we know , for any quadratic have real roots only when Discriminant=b² -4ac ≥0
D = b² -4ac =(9)² -4 x 7 x 6
D = 81 -168 = -87 <0
hence, no real roots exist of 7x²+9x +6
hence, we can't factorise ,
so, simplest form of this is ------
10x(7x² +9x + 6)
10x (7x²) +10x(9x)² + 10x(6)²
70x³ +90x² + 60x this is simplest form of given expression .