The sum of 8 times a number and 7.....sum means add
8n + 7
is twice the number...is means equals
= 2n
so we have : 8n + 7 = 2n
Let's simplify step-by-step. <span>7−<span>4<span>(<span>3−<span>(<span><span>4y</span>−5</span>)</span></span>)</span></span></span>
<span><span><span /></span></span>Distribute:<span> =<span><span><span>7+<span><span>(<span>−4</span>)</span><span>(3)</span></span></span>+<span><span>(<span>−4</span>)</span><span>(<span>−<span>4y</span></span>)</span></span></span>+<span><span>(<span>−4</span>)</span><span>(5)</span></span></span></span><span>=<span><span><span><span><span>7+</span>−12</span>+<span>16y</span></span>+</span>−20</span></span>
<span><span /></span>Combine Like Terms: <span>=<span><span><span>7+<span>−12</span></span>+<span>16y</span></span>+<span>−20</span></span></span><span>=<span><span>(<span>16y</span>)</span>+<span>(<span><span>7+<span>−12</span></span>+<span>−20</span></span>)</span></span></span><span>=<span><span>16y</span>+<span>−25</span></span></span>
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<span><span><span /></span></span>Answer: <span>=<span><span>16y</span>−<span>25</span></span></span>
<em>Step #1: </em>
Make sure the equation is in the form of [ Ax² + Bx + C = 0 ].
Yours is already in that form.
A = 1
B = 2
C = -2
<em>Step #2:</em>
The 'discriminant' for that equation is [ B² - 4 A C ].
That's all there is to it, but it can tell you a lot about the roots of the equation.
-- If the discriminant is zero, then the left side of the equation is a perfect square,
and both roots are equal.
-- If the discriminant is greater than zero, the the roots are real and not equal.
-- If the discriminant is less than zero, then the roots are complex numbers.
The discriminant of your equation is [ B² - 4 A C ] = 2² - 4(1)(-2) = 4 + 8 = 12
Your equation has two real, unequal roots.
2rd one I could be wrong tho
