Math which one is right? Giving brainlist

Mathematics

1 answer:

N76 [4]3 years ago

6 0

Answer:

Third option.

Step-by-step explanation:

$5-2\left(3x-9\right)=-1$

Use the distributive law: $a(b-c)=ab-ac$

$5-2\times3x-\left(-2\right)\times9=-1$

Double negative = Positive

$5-6x+18=-1$

You might be interested in

Solve for x.

Ivahew [28]

ANSWER

$x=\frac{2-\sqrt{10}} {3}$

or

$x=\frac{\sqrt{10}+2} {3}$

We have

$3x^2-4x-2=0$

Since we cannot factor easily, we complete the square.

Adding 2 to both sides give,

$3x^2-4x=2$

Dividing through by 3 gives

$x^2-\frac{4}{3}x= \frac{2}{3}$

Adding $(-\frac{2}{3})^2$ to both sides gives

$x^2-\frac{4}{3}x+(-\frac{2}{3})^2= \frac{2}{3}+(-\frac{2}{3})^2$

The expression on the Left Hand side is a perfect square.

$(x-\frac{2}{3})^2= \frac{2}{3}+\frac{4}{9}$

$\Rightarrow (x-\frac{2}{3})^2= \frac{10}{9}$

$\Rightarrow (x-\frac{2}{3})=\pm \sqrt{\frac{10}{9}}$

$\Rightarrow (x)=\frac{2}{3} \pm {\frac{\sqrt{10}}{3}$

Splitting the plus or minus sign gives

$x=\frac{2- \sqrt{10}} {3}$

or

$x=\frac{\sqrt{10}+2} {3}$

3 0

3 years ago

Read 2 more answers

30. Felipe va a hacer un banderín para su equipo de fútbol, con las medidas que se indican en la figura. ¿Cuánta tela ocupará pa

blagie [28]

Veremos que el area del banderín es 930cm^2, entonces la opción correcta es A.

<h3>¿Que area tiene el banderin?</h3>

Luego de una pequeña busqueda online, pude ver que el banderin es un triangulo isósceles con base de 31cm y altura de 60 cm.

Recordar que para un triangulo de base b y altura h, el area es:

A = b*h/2

Entonces el area del banderín va a ser:

A = (31cm)*(60cm)/2 = 930cm^2