Simplify 6z^-7 (2) x² (4) ^4x^-4

Step-by-step explanation:

First, subtract  

7

from each side of the equation to put the equation in standard form:

x

2

+

4

x

+

4

−

7

=

7

−

7

x

2

+

4

x

−

3

=

0

We can now use the quadratic formula to find the solutions for  

x

. The quadratic formula states:

For  

a

x

2

+

b

x

+

c

=

0

, the values of  

x

which are the solutions to the equation are given by:

x

=

−

b

±

√

b

2

−

(

4

a

c

)

2

⋅

a

Substituting:

1

for  

a

4

for  

b

−

3

for  

c

gives:

x

=

−

4

±

√

4

2

−

(

4

⋅

1

⋅

−

3

)

2

⋅

1

x

=

−

4

±

√

16

−

(

−

12

)

2

x

=

−

4

±

√

16

+

12

2

x

=

−

4

±

√

28

2

x

=

−

4

±

√

4

⋅

7

2

x

=

−

4

±

√

4

√

7

2

x

=

−

4

±

2

√

7

2

x

=

−

4

2

±

2

√

7

2

x

=

−

2

±

√

7

Or

x

=

−

2

+

√

7

and  

x

=

−

2

−

√

7

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18

the correct option is 2.

step-by-step explanation:

according to the given information triangle abc is a right angle triangle with right angle at a. segment ab is 5 and segment ac is 7. point d is on segment bc and angles adb and adc are right angles.

it is given that triangles abd, cad, and cba are similar.

two triangles are similar if their corresponding sides are proportional.

in triangle cba, using pythagoras theorem

                      )

triangle abd and cba are similar,

                            (2)

triangle cad and cba are similar,

                      )

using (1), (2) and (3), we get

hence proved.

therefore option 2 is correct.