$15.\ \text{Elimination method}\\\underline{+\left\{\begin{array}{ccc}y=-3x+9\\y=3x+3\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad2y=12\qquad\text{divide both sides by 2}\\.\qquad \boxed{y=6}\\\\\text{put the value of y to the second equation}\\\\6=3x+3\qquad\text{subtract 3 from both sides}\\3=3x\qquad\text{divide both sides by 3}\\1=x\to\boxed{x=1}\\\\Answer:\ x=1,\ y=6\to(1,\ 6)$

$16.\ \text{Substitution method}\\\left\{\begin{array}{ccc}y=11x+4\\y=7x-16\end{array}\right\Rightarrow11x+4=7x-16\\\\11x+4=7x-16\qquad\text{subtract 4 from both sides}\\11x=7x-20\qquad\text{subtract 7x from both sides}\\4x=-20\qquad\text{divide both sides by 4}\\\boxed{x=-5}\\\\\text{Put the value of x to the first equation}\\\\y=11(-5)+4\\y=-55+4\\\boxed{y=-51}\\\\Answer:\ x=-5,\ y=-51\to(-5,\ -51)$

7 0

3 years ago

Read 2 more answers

7) what is the BEST conclusion we can draw from the graph <br><br> (the answers are in the picture)

Viktor [21]

Answer:

Step-by-step explanation:

7 0

3 years ago

Solve for x, given the equation Square root of x plus 9 − 4 = 1.

yuradex [85]

√x + 9 - 4 = 1
√x + 5 = 1
√x = -4
√x = √-4
x = 2i

3 0

2 years ago

Read 2 more answers

Area triangles? it says show work so pls do

coldgirl [10]

$\large{\underline{\underline{\pmb{\sf {\color {blue}{Solution:}}}}}}$

Given,

Area = 225 yd²

Base = 30 yd

Height = [To be calculated]

To find:

The height of the given triangle.

We know that, area of a triangle is:

$\frac{1}{2} \times (b \times h) \\ \\ \leadsto \frac{1}{2} \times (30 \times h) \\ \\ \leadsto \frac{1}{2} \times 30h \\ \\ \leadsto \frac{1}{ \cancel{2}} \times \cancel{30}h \\ \\ \leadsto1 \times 15h \\ \\ \leadsto \: h = 15 \: yd$

Therefore, the require height is 15 yd.

$\green\star$ Proof:

$\frac{1}{2} \times (b \times h) \\ \\ \leadsto \frac{1}{2} \times (30 \times 15) \\ \\ \leadsto \frac{1}{ \cancel{2}} \times \cancel{450} \\ \\ \leadsto1 \times 225 \\ \\ area = 225 {yd}^{2}$

$\boxed{ \frak \red{brainlysamurai}}$

6 0

1 year ago