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Overview: 1 questions will be solved this time.Among them ☆1 equations
[ 1/1 Equation] Work: Find the solution of equation (x−7)(x−4) = 0 . Question type: Equation Solution:Original question:
(
x
−
7
)
(
x
−
4
)
=
0
Remove the bracket on the left of the equation:
Left side of the equation =
x
(
x
−
4
)
−
7
(
x
−
4
)
=
x
x
−
x
×
4
−
7
(
x
−
4
)
=
x
x
−
4
x
−
7
x
+
7
×
4
=
x
x
−
4
x
−
7
x
+
28
=
x
x
−
11
x
+
28
The equation is transformed into :
x
x
−
11
x
+
28
=
0
After the equation is converted into a general formula, it is converted into: ( x - 4 )( x - 7 )=0 From x - 4 = 0 x - 7 = 0 it is concluded that:: x1=4 x2=7 There are 2 solution(s).