\(\left(7x+3\right)^2-\left(7x-1\right)\left(7x-3\right)=-12\)
\(\Rightarrow49x^2+42x+9-\left(49x^2-21x-7x+3\right)=-12\)
\(\Rightarrow70x+18=0\) \(\Rightarrow x=-\dfrac{18}{70}=-\dfrac{9}{35}\)
\(\left(7x+3\right)^2-\left(7x-1\right)\left(7x-3\right)=-12\)
\(\Rightarrow49x^2+42x+9-\left(49x^2-21x-7x+3\right)=-12\)
\(\Rightarrow70x+18=0\) \(\Rightarrow x=-\dfrac{18}{70}=-\dfrac{9}{35}\)
tìm x
a) 4x (7x-5)-7x (4x-2)=-12
b) (x+3) (x-2) +3x=4(x+¾)
Tìm x
a)5x(1/5x-2)+3(6-1/3x2)=12
b)7x(x-2)-5(x-1)=7x2+3
c)2(5x-8)-3(4x-5)=4(3x-4)+11
(12x + 7)2(3x +2)(2x+1)=3
⇔ (12²x²+2.12.7x + 7²)(6x²+7x+2) = 3
⇔ [24.(6x² +7x +2) +1].(6x² +7x +2) =3
đặt: a= 6x² +7x +2
⇔ (24a+1).a = 3
⇔ (3a-1)(8a+3)=0
⇔ a=1/3 hoặc a=−3/8
chang pit lam nua??????????/
tìm x biết
7x(x-2)-5(x-1)=7x mũ 2+3
giải phương trinh sau
1/ x^2 +7x +6 =0
2/ x^2 +7x +12 =0
3/ x^2 +8x+15 =0
4/ x^2 +5x+4 =0
1. TÌm x:
a)4x^2-2x+3-4x.(x-5)=7x-3
b)-3x.(x-5)+5.(x-1)+3x^2=4x
c)7x.(x-2)-5.(x-1)=21x^2-14x^2+3
d)3.(5x-1)-x.(x-2)+x^2-13x=7
e) 1/5x.(10x-15)-2x.(x-5)=12
1. TÌm x:
a)4x^2-2x+3-4x.(x-5)=7x-3
b)-3x.(x-5)+5.(x-1)+3x^2=4x
c)7x.(x-2)-5.(x-1)=21x^2-14x^2+3
d)3.(5x-1)-x.(x-2)+x^2-13x=7
e) 1/5x.(10x-15)-2x.(x-5)=12
tìm x biết
e, ( 9x\(^2\)- 49)+ (3x + 7 ) ( 7x+3) = 0
g, ( x - 4)\(^2\)= ( 2x-1)\(^2\)
h, x\(^2\)- x\(^2\)+ x - 1 = 0
i, x + x\(^2\)+ x + 1 = 0
k, x(x+ 16) - 7x - 42 = 0
m, x\(^2\)+ 7x + 12 = 0
n, x\(^2\)- 7x + 12 = 0