Which system of equations has a solution of approximately (0.7, –1.4)?

50x² + 35x - 49 = 0

Step-by-step explanation:

x = 0.7 or x = -1.4

We have to convert the improper fraction value of the roots. (You can use your calculator to save time)

x = 7/10 or x = - 7/5

x - 7/10 = 0 or x + 7/5 = 0

(x -7/10)(x + 7/5) = 0

multiply through the bracket

x² + (7/5x - 7/10x) - 49/50 = 0

x² + 7/10x - 49/50 = 0

Multiply through by 50 to eliminate the fraction from the equation

50x² + 35x - 49 = 0

50x² + 35x - 49 = 0 is the equation that satisfies the root x = 0.7 or x = -1.4

the value of v.w= -12.

step-by-step explanation:

we are given three vector r,v and w as:

r = < 5, -5, -2> ; v = < 2, -8, -8> ; w = < -2, 6, -5>

we know that r,v and w could also be represented as:

r=5i-5j-2k

v=2i-8j-8k

and w= -2i+6j-5k

where i,j and k are the unit vectors of x,y and z-axis respectively.

also we know that it has the following property:

i.i=1 ; j.j=1; k.k=1

and i.=j.i=i.k=k.i=j.k=k.j=0

i.e. when we multiply two vectors or we find it's dot product we need to only multiply the components of x coordinates with each other; y with each other and z with each other.

hence, v.w= (2i-8j- -2i+6j-5k)

                  = 2×(-2)+(-8)×(6)+(-8)×(-5)

                  = -4-48+40

                  = -12

hence, v.w= -12

none cuz there are no "following statements" regarding the question

step-by-step explanation: