Current time:0:00Total duration:2:21
0 energy points
Studying for a test? Prepare with these 10 lessons on Quadratic equations and functions.
See 10 lessons
Video transcript
Rewrite the equation 6x^2 + 3 = 2x - 6 in standard form and identify a, b, and c. So standard form for a quadratic equation is ax squared plus bx plus c is equal to zero. So essentially you wanna get all of the terms on the left-hand side, and then we want to write them so that we have the x terms...where their exponents are in decreasing order. So we have the x squared term and then the x term and then we have the constant term. So let's try to do this over here. So let me rewrite our original equation. We have 6x squared plus 3 is equal to 2x minus 6. So essentially we wanna get everything on the left-hand side. so I could subtract 2x from both sides, so I could subtract 2x from both sides, so let me just...I'll take one step at a time. So I can subtract 2x from both sides. And then I'll get...and I'm gonna write it in descending order for the exponents on x. So the highest exponent is x squared. So I'll write that first. 6x squared, and then we have minus 2x, and then we have plus 3 is equal to... the 2 'x's on the right cancel out...equal to negative 6. And now, to get rid of this negative 6 on the right-hand side, we can add 6 to both sides. So let's add 6 to both sides... ...and then this simplifies to 6x squared, minus 2x, plus nine is equal So let's make sure we're already in standard form. All of our terms, our non-zero terms are on the left-hand side, we've done that. We have a zero on the right-hand side, we've done that. And, we have the x squared term first, then the x to the first power term, then the constant term. x squared, then x to the first, then the constant term. So we are in standard form. And so we can say that a is equal to 6, a is equal to 6. We could say that b is equal to, and this is key, it's not just the 2, it's the negative 2. B is equal to negative 2, 'cause notice this says plus bx, but over here we have minus 2x. So the b is a negative 2 here. B is negative 2. And then c, c is going to be, c is going to be 9.