Subtract 2x^2+6x-5from7x^2+3x+4

Solve algebraically please URGENT y=5x−7 −6x−4y=−24

Kazeer [188]

$\left\{\begin{array}{ccc}y=5x-7\\-6x-4y=-24&\text{divide both sides by (-2)}\end{array}\right\\\left\{\begin{array}{ccc}y=5x-7&(*)\\3x+2y=12&(**)\end{array}\right\\\\\text{substitute }\ (*)\ \text{to}\ (**):\\\\3x+2(5x-7)=12\qquad\text{use distributive property}\\\\3x+(2)(5x)+(2)(-7)=12\\\\3x+10x-14=12\qquad\text{add 14 to both sides}\\\\13x=26\qquad\text{divide oth sides by 13}\\\\\boxed{x=2}\\\\\text{Put the vaalue of x to}\ (*):\\\\y=5(2)-7\\\\y=10-7\\\\\boxed{y=3}\\\\Answer:\ \boxed{x=2\ and\ y=3\to(2,\ 3)}$

7 0

3 years ago

Find the distance between the two points in simplest radical form. (-9,8) and (-3, -1)

dmitriy555 [2]

Answer:

The distance between (-9, 8) and (-3, -1) will be:

$\:d=3\sqrt{13}$ units

Step-by-step explanation:

Given the points

(-9, 8)

(-3, -1)

Finding the distance between (-9, 8) and (-3, -1)

$d\:=\sqrt{\left(x_2-x_1\right)^2+\left(y_2-y_1\right)^2}$

$=\sqrt{\left(-3-\left(-9\right)\right)^2+\left(-1-8\right)^2}$

$=\sqrt{\left(-3+9\right)^2+\left(-1-8\right)^2}$

$=\sqrt{36+81}$

$=\sqrt{117}$

$=3\sqrt{13}$ units

Therefore, the distance between (-9, 8) and (-3, -1) will be:

$\:d=3\sqrt{13}$ units

7 0

2 years ago

The graph below shows the height of a projectile t seconds after it is launched. If acceleration due to gravity is –16 ft/s2, wh

nika2105 [10]

Answer:

see attached

Step-by-step explanation:

The x-coordinate of the vertex is given by ...

x = -b/(2a)

for f(x) = ax^2 +bx +c.

We see that the vertex is at x = 1, and we are given a = -16. Then we can find "b" from ...

1 = -b/(2(-16))

32 = b

We know the y-intercept of the equation is 5 (the starting height), so the equation must be ...

h(t) = -16t^2 +32t +5 . . . . . matches the last choice

5 0

3 years ago

2/x + 3/y = 13 ; 5/x - 4/y = -2

Tomtit [17]

Given that

(2/x)+(3/y) = 13--------(1)

(5/x)-(4/y) = -2 -------(2)

Put 1/x = a and 1/y = b then

2a + 3b = 13 ----------(3)

On multiplying with 5 then

10a +15 b = 65 -------(4)

and

5a -4b= -2 ----------(5)

On multiplying with 2 then

10 a - 8b = -4 -------(6)

On Subtracting (6) from (4) then

10a + 15b = 65

10a - 8b = -4

(-)

_____________

0 + 23 b = 69

______________

⇛ 23b = 69

⇛ b = 69/23

⇛ b =3

On Substituting the value of b in (5)

5a -4b= -2

⇛ 5a -4(3) = -2

⇛ 5a -12 = -2

⇛ 5a = -2+12

⇛ 5a = 10

⇛ a = 10/5

⇛ a = 2

Now we have

a = 2

⇛1/x = 2

⇛ x = 1/2

and

b = 3

⇛1/y = 3

⇛ y = 1/3

Answer :-The solution for the given problem is (1/2,1/3)

Check: If x = 1/2 and y = 1/3 then

LHS = (2/x)+(3/y)

= 2/(1/2)+3/(1/3)

= (2×2)+(3×3)

= 4+9

= 13

= RHS

LHS=RHS is true

and

LHS=(5/x)-(4/y)

⇛ 5/(1/2)- 4/(1/3)

⇛(5×2)-(4×3)

⇛ 10-12

⇛ -2

⇛RHS

LHS = RHS is true

5 0

2 years ago

Arjun solved the equation 7·m=56 His work is shown. What error did Arjun make?

natulia [17]

He multiplied rather than dividing.

$\mathrm{Divide\:both\:sides\:by\:}7 \ \textgreater \ \frac{7m}{7}=\frac{56}{7} \ \textgreater \ Simplify \ \textgreater \ m = 8$

Hope this helps!

6 0

2 years ago

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