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2 years ago

**Solve by Elimination 3 + 2x - y = 0 -3-7y = 10x 7) x = 8) y =

1 answer:

7 0

Answer:

Explanation:

3 + 2x - y = 0
Or 2x - y = -3 (1)

-3-7y = 10x
Or -10x - 7y = 3 (2)

2x - y = -3 (1)
-10x - 7y = 3 (2)
———————

Multiply 5 to (1)

5(2x - y = -3)
-10x - 7y = 3
———————
10x - 5y = -15
-10x - 7y = 3
———————
-12y = -12
y = -12/-12
y = 1

Plug y value in (1)

2x - 1 = -3
2x = -3 + 1
2x = -2
x = -2/2 = -1

Therefore, x = -1 and y = 1

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Nuts.com sells raw almonds for $10 per pound and roasted pistachios for $12 per pound. Christopher spends $70, before taxes and

sp2606 [1]

Christopher purchased 2.8 pounds of almonds and 3.5 pounds to roasted pistachios.

Step-by-step explanation:

Cost of almonds per pound = $10

Cost of roasted pistachios = $12

Total amount spent = $70

Weight of nuts = 6.3

Let,

Weight of almonds = x

Weight of roasted pistachios = y

According to given statement;

x+y=6.3 Eqn 1

10x+12y=70 Eqn 2

Multiplying Eqn 1 by 10

$10(x+y=6.3)\\10+10y=63\ \ \ Eqn\ 3$

Subtracting Eqn 3 from Eqn 2;

$(10x+12y)-(10x+10y)=70-63\\10x+12y-10x-10y=7\\2y=7$

Dividing both sides by 2

$\frac{2y}{2}=\frac{7}{2}\\y=3.5$

Putting y=3.5 in Eqn 1

$x+3.5=6.3\\x=6.3-3.5\\x=2.8$

Christopher purchased 2.8 pounds of almonds and 3.5 pounds to roasted pistachios.

Keywords: linear equations, elimination method

Learn more about elimination method at:

#LearnwithBrainly

8 0

2 years ago

Pls help trig question!!

s2008m [1.1K]

$4\sin^2 x - 3 = 3 \sin x\\\\\implies 4\sin^2 x -3 \sin x -3 =0\\\\\implies 4u^2 -3u -3 =0~~~~~~~~~~~~~~;[\text{Set} ~ \sin x = u]\\\\\implies u = \dfrac{-(-3) \pm \sqrt{(-3)^2 - 4\cdot 4 \cdot (-3)}}{2(4)}~~~~~~;[\text{Apply quadratic formula}]\\\\\\\implies u = \dfrac{3\pm\sqrt{57}}8\\\\\implies \sin x = \dfrac{3\pm\sqrt{57}}8~~~~~~;[\text{Substitute back}~ u = \sin x]\\\\\text{Now,}\\\\\sin x = \dfrac{3+\sqrt{57}}8\\\\\text{No solution for}~ x\in \mathbb{R} ~\text{Since}~ -1\leq \sin x \leq 1\\$

$\sin x = \dfrac{3 - \sqrt{57}}8\\\\\implies x = n\pi + (-1)^n \sin^{-1} \left(\dfrac{3-\sqrt{57}}8\right)\\\\\\\text{ When n = 1,2 and}~ [0,2\pi]},\\\\\\x= \pi - \sin^{-1} \left(\dfrac{3-\sqrt{57}}8 \right)~ \text{and} ~x = 2\pi + \sin^{-1} \left(\dfrac{3-\sqrt{57}}8 \right)\\\\\text{In decimal,}\\\\x= 3.75~~~~ \text{and}~~~ x =5.68$

5 0

1 year ago

Which is greater 11/16 or 3/4

Anettt [7]

To compare fractions, we need to have the same denominator
The least common multiple is 16
$\frac{11}{16}$
to change $\frac{3}{4}$ , we should multiply the numerator and denominator by 4
$\frac{3*4}{4*4}$ = $\frac{12}{16}$

$\frac{11}{16}$ < $\frac{12}{16}$

so basically, $\frac{12}{16}$ is greater than $\frac{11}{16}$
which means $\frac{3}{4}$ is greater

$\frac{3}{4}$ is greater

6 0

2 years ago

The answers to A,B,C,D

scoundrel [369]

Answer:

Step-by-step explanation:

7 0

2 years ago

2. Aaron baked two identical cakes. He cut one into 9 equal slices and the other into 19 equal slices.

Svetlanka [38]

2/3 x 9 = 6 slices

1/3 x 18 = 6 slices

Hence they give the same number of slices.

5 0

2 years ago