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3 years ago

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(6x - 5y = 34 Lin is solving this system of equations: 3x +2y = 8 She starts by rearranging the second equation to isolate the y

variable: y = 4-1.5x. She then substituted the expression 4 - 1.5x for y in the first equation, as shown: 6x - 5(4- 1.5x) 6x - 20 – 7.5x -1.5x 34 = 34 = 54 = -36 Where did Lin go wrong when solving this problem?

1 answer:

Norma-Jean [14]3 years ago

4 0

Answer:

It is a little hard to see where your steps are for the equation, but x = 4, and I will explain:

Step-by-step explanation:

We know y = -1.5x +4, so we plug that into the equation

6x - 5(-1.5 + 4) = 34

6x +7.5x - 20 = 34 Here we distributed the -5 into the parenthesis.

13.5x -20 = 34

13.5 = 54

x = 4

Hope this helps!

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Can someone do this plz??

Maksim231197 [3]

Answer:

$x = - 6$

$x = 12$

$x = 8$

$x = - 21$

$x = 18$

$x = - 2$

$x = 40$

$x = - 3$

$x = -21$

$x = 2$

$x = - 18$

$x = - 7$

$x = 6$

$x = 10$

$x = 3$

Step-by-step explanation:

$1.$

$- 7x + 16 = 58$

$- 7x = 58 - 16$

$- 7x = 42$

$\frac{ - 7x}{ - 7} = \frac{42}{ - 7}$

$x = \frac{ 42}{ - 7}$

$x = - 6$

$2.$

$- 2x + 15 = - 9$

$- 2x = - 9 - 15$

$- 2x = - 24$

$\frac{ - 2x}{ - 2} = \frac{ - 24}{ - 2}$

$x = \frac{ - 24}{ - 2}$

$x = 12$

$3.$

$5x - 4 = 36$

$5x = 36 + 4$

$5x = 40$

$\frac{5x}{5} = \frac{40}{5}$

$x = \frac{40}{5}$

$x = 8$

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$25 - 3x = 88$

$- 3x = 88 - 25$

$- 3x = 63$

$\frac{ - 3x}{ - 3} = \frac{63}{ - 3}$

$x = \frac{63}{ - 3}$

$x = - 21$

$5.$

$- 11 = 7 - x$

$7 - x = - 11$

$- x = - 11 - 7$

$- x = - 18$

$\frac{ - x}{ - 1} = \frac{ - 18}{ - 1}$

$x = \frac{ - 18}{ - 1}$

$x = 18$

$6.$

$65 + 15x = 35$

$15x = 35 - 65$

$15x = - 30$

$\frac{15x}{15} = \frac{ - 30}{15}$

$x = \frac{ - 30}{15}$

$x = - 2$

$7.$

$\frac{1}{2} x - 18 = 2$

$\frac{1}{2} x = 2 + 18$

$\frac{1}{2} x = 20$

$\frac{1}{2} \times 2x = 20 \times 2$

$x = 40$

$8.$

$\frac{2}{3} x - 10 = - 12$

$\frac{2}{3} x = - 12 + 10$

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

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

$x = - 3$

$9.$

$6 - \frac{1}{3} x = - 1$

$- \frac{ 1}{3} x = - 1 - 6$

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$x = - 7( - \frac{3}{1} x)$

$x = 21$

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$-9x = - 18$

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$x = \frac{ - 18}{-9}$

$x = 2$

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$- x = 29 - 11$

$- x = 18$

$\frac{ - x}{ - 1} = \frac{18}{ - 1}$

$x = \frac{ 18}{ - 1}$

$x = - 18$

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$\frac{ - 11x}{ - 11} = \frac{77}{ - 11}$

$x = \frac{77}{ - 11}$

$x = - 7$

$13.$

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$\frac{5}{6} x = 50 - 45$

$\frac{5}{6} x = 5$

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$14.$

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$- 5x = - 33 - 17$

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$\frac{ - 5x}{ - 5} = \frac{ - 50}{ - 5}$

$x = \frac{ - 50}{ - 5}$

$x = 10$

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$- 4 + 33x = 95$

$33x = 95 + 4$

$33x = 99$

$\frac{33x}{33} = \frac{99}{33}$

$x = \frac{99}{33}$

$x = 3$

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