write an equation for one fifth of a number n is equal to -7 is the equation true, false or an open sentence

b) yes

step-by-step explanation:

let the statements be named as,

statement 1: if the power has been cut, then the refrigerator does not work.

statement 2: the refrigerator does not work.

conclusion: the power has been cut

now, 'law of detachment states that if we have the statements given as,

1. if p, then q.

2. p

then, we get the true statement or conclusion as q'.

thus, on comparing, we get that,

p: if the power has been cut.

q: the refrigerator does not work.

so, the argument is true by the law of detachment.

it is given that, b ≅ bc and ad ≅ cd  

we need bd perpendicular to ac, then only we can say   triangles axb and cxb are congruent using the hl theorem.

if bd perpendicular to ac, means that ab and cb are the hypotenuse of triangles axb and cxb respectively.

from the given information abcd is a square

if bd and ac bisect each other then ax = cx

then only we can   immediately possible to prove that triangles axd and cxd are congruent by sss congruence theorem.