(х-2)*(х²+8х+16)=7*(х+4)

Лебедев Дмитрий Сергеевич

Учитель математики

Проверено учителем

To solve the equation (x2)(x2+8x+16)=7(x+4)open paren x minus 2 close paren open paren x squared plus 8 x plus 16 close paren equals 7 open paren x plus 4 close paren, we will simplify the expressions, factor where possible, and find the roots. 1. Simplify the Quadratic Expression Notice that x2+8x+16x squared plus 8 x plus 16 is a perfect square trinomial. It follows the pattern a2+2ab+b2=(a+b)2a squared plus 2 a b plus b squared equals open paren a plus b close paren squared: x2+8x+16=(x+4)2x squared plus 8 x plus 16 equals open paren x plus 4 close paren squaredSubstituting this back into the equation: (x2)(x+4)2=7(x+4)open paren x minus 2 close paren open paren x plus 4 close paren squared equals 7 open paren x plus 4 close paren2. Move all terms to one side To avoid losing potential solutions by dividing by (x+4)open paren x plus 4 close paren, we move everything to the left side to set the equation to zero: (x2)(x+4)27(x+4)=0open paren x minus 2 close paren open paren x plus 4 close paren squared minus 7 open paren x plus 4 close paren equals 03. Factor out the common term Both terms share a factor of (x+4)open paren x plus 4 close paren. Let's factor it out: (x+4)[(x2)(x+4)7]=0open paren x plus 4 close paren center dot open bracket open paren x minus 2 close paren open paren x plus 4 close paren minus 7 close bracket equals 04. Simplify the expression inside the brackets Expand the product (x2)(x+4)open paren x minus 2 close paren open paren x plus 4 close paren: (x2)(x+4)=x2+4x2x8=x2+2x8open paren x minus 2 close paren open paren x plus 4 close paren equals x squared plus 4 x minus 2 x minus 8 equals x squared plus 2 x minus 8Now substitute this back into the brackets: (x+4)(x2+2x87)=0open paren x plus 4 close paren open paren x squared plus 2 x minus 8 minus 7 close paren equals 0 (x+4)(x2+2x15)=0open paren x plus 4 close paren open paren x squared plus 2 x minus 15 close paren equals 05. Find the roots An equation is equal to zero if any of its factors are zero. Factor 1: x+4=0x1=-4x plus 4 equals 0 ⟹ bold x sub 1 equals negative 4Factor 2: x2+2x15=0x squared plus 2 x minus 15 equals 0We can solve this quadratic equation using the quadratic formula or by factoring. Seeking two numbers that multiply to -15negative 15 and add to 22, we find 55 and -3negative 3: (x+5)(x3)=0open paren x plus 5 close paren open paren x minus 3 close paren equals 0This gives us the remaining roots: x+5=0x2=-5x plus 5 equals 0 ⟹ bold x sub 2 equals negative 5 x3=0x3=3x minus 3 equals 0 ⟹ bold x sub 3 equals 3Answer: The solutions to the equation are x=-5,-4,3x equals negative 5 comma negative 4 comma 3. Would you like me to verify these solutions by substituting them back into the original equation?

Форма ответа

Ваш аватар