Solve 7x^2–20x = 3. ;

Mathematics

2 answers:

valentinak56 [21]3 years ago

7 0

Answer:

$x = \frac{-1}{7}$ <em>or </em> $x = 3$ <em />

sasho [114]3 years ago

3 0

Answer:

x=3, -1/7

Step-by-step explanation:

7x^2-20x-3=0

Factor.

(x-3)(7x+1)=0

x-3=0 ⇒ x=3

7x+1=0 ⇒7x=-1 ⇒x= -1/7

You might be interested in

I need help..What’s the answer

RSB [31]

Answer:

D. 3,750

Step-by-step explanation:

Use proportions to solve:

125/500 = x/15000

Cross multiply:

125*15000 = 1,875,000

1,875,000/500 = 3,750

x = 3,750

6 0

3 years ago

2.1 & 2.2 Assessment: Vertex & Standard Form of Quadratic Functions

Brums [2.3K]

$~~~~~~\textit{vertical parabola vertex form} \\\\ y=a(x- h)^2+ k\qquad \begin{cases} \stackrel{vertex}{(h,k)}\\\\ \stackrel{"a"~is~negative}{op ens~\cap}\qquad \stackrel{"a"~is~positive}{op ens~\cup} \end{cases} \\\\[-0.35em] ~\dotfill$

$\begin{cases} h=1\\ k=-9 \end{cases}\implies y=a(x-1)^2 - 9\qquad \textit{we also know that} \begin{cases} x=2\\ y=-7 \end{cases} \\\\\\ -7=a(2-1)^2-9\implies 2=a(1)^2\implies 2=a \\\\[-0.35em] ~\dotfill\\\\ ~\hfill {\Large \begin{array}{llll} y=2(x-1)^2 -9 \end{array}} ~\hfill$

6 0

1 year ago

How many extraneous solutions does the equation below have?

aev [14]

Answer:

A solution is said to be extraneous, if it is a zero of the equation, but it does not satisfy the equation,when substituted in the original equation,L.H.S≠R.H.S.

The given equation consisting of variable , m is

$\frac{2 m}{2 m+3} -\frac{2 m}{2 m-3}=1\\\\ 2 m[\frac{1}{2 m+3} -\frac{1}{2 m-3}]=1\\\\ 2 m\times \frac{[2 m-3 -2 m- 3]}{4m^2-9}=1\\\\ -6 \times 2 m=4 m^2 -9\\\\ 4 m^2 +1 2 m -9=0\\\\m=\frac{-12 \pm\sqrt{12^2-4 \times 4 \times (-9)}}{2\times 4}\\\\m=\frac{-12 \pm \sqrt {144+144}}{8}\\\\m=\frac{-12 \pm \sqrt {288}}{8}\\\\m=\frac{-12 \pm 12 \sqrt{2}}{8}\\\\m=\frac{3}{2}\times(-1 \pm \sqrt{2})$