Solve by using the quadratic formula. Please Show All Work!
4x(x+3)=15
I'm not quite sure how this one would be done. I tried to figure it out for you. However this is the answer I'm getting.
4x(x+3)=15
4x(1x)+12x=15
4 times 1 is 4+12=16
Sorry, I tried to help you but I'm having issues in Algebra too and I have a few on here I haven't got help with yet
Rewrite it in standard format for quadratic equations, ax^2 + bx + c = 0.
In your case,
4x^2 +12x -15 = 0
so a = 4, b = 12 and c = -15.
Now apply the quadratic equation to get the two solutions. If you don't know what that is, it's time you learned it. It should be easy to find in your textbook or online.
To solve the equation 4x(x + 3) = 15 using the quadratic formula, we first need to rearrange the equation to have a quadratic term on one side and a constant term on the other side.
1. Start by distributing 4x to the terms inside the parentheses:
4x * x + 4x * 3 = 15
2. Simplify:
4x² + 12x = 15
3. Move the constant term to the other side:
4x² + 12x - 15 = 0
Now, we can identify the values of a, b, and c in the quadratic formula: ax² + bx + c = 0.
In this case:
a = 4
b = 12
c = -15
The quadratic formula is:
x = (-b ± √(b² - 4ac)) / 2a
4. Substitute the values of a, b, and c into the formula:
x = (-12 ± √(12² - 4 * 4 * -15)) / (2 * 4)
5. Simplify inside the square root:
x = (-12 ± √(144 + 240)) / 8
x = (-12 ± √384) / 8
6. Simplify the square root, if possible. In this case, 384 can be simplified as √(384) = √(64 * 6) = 8√6.
x = (-12 ± 8√6) / 8
7. Further simplify the expression by factoring out 4 from the numerator:
x = (-12 ± 8√6) / 8
x = -3 ± 2√6
Therefore, the solutions to the equation 4x(x + 3) = 15, using the quadratic formula, are:
x = -3 + 2√6 or x = -3 - 2√6.