Please help, I don't understand this​

After substitution in the first equation :

7x + x +21 = -19

= 8x + 21 = -19

by subtracting 21 :

8x = -19 - 21

8x = -40

by dividing over 8 :

x = -5

after substitution in the second equation :

2y = -5 + 21

2y = 16

by dividing over 2 :

y = 8

pls give me brainliest

option a, c,d are correct.

step-by-step explanation:

from the given figure, it is given that z is equidistant from the sides of the triangle rst, then from triangle tzb and triangle szb, we have

tz=sz(given)

bz=zb(common)

therefore, by rhs rule,δtzb ≅δszb

by cpctc, sz≅tz

also, from δctz and δasz,

tz=sz(given)

∠tcz=∠saz(90°)

by rhs rule, δctz ≅ δasz, therefore by cpctc, ∠ctz≅∠asz

also,from δasz and δzsb,

zs=sz(common)

∠zbs=∠saz=90°

by rhs rule, δasz ≅δzsb, therefore, by cpctc, ∠asz≅∠zsb

hence, option a, c,d are correct.

did you get the answer yet?

step-by-step explanation: