Solve the expression!!

x = 2 y = 6 z = 4
1. 2x + y =

thus put the value of x and y in your expression:

2(2) +6 =10

again put the values of x and z:

6+2*4 = 14

out values of x and z:

(1/2)(2*2 +4) = (1/2)(8) = 4

put values of x and z:

(6+2) *2 -4 = 16-4 =12

you're in a mistake: multiply 2 by(6+2) => 2*8 =16
then rest from 16 the number 4 => 16-4 =12

if you mean (6+x)*(x-z) => (6+2)(2-4) = 8 (-2) =-16 like you said and of course that a negative number does exist

4 +x(y-z) => 4 +2(6-4) => 4 +2*2 = 8

a=3 , b=6 , c=4

16 -a² +c = 16 -3² +4 = 16-9+4 = 11

ab -4 => 3*6 -4 = 18-4 =14 which means that you're right.

b-2a+7 = > 6 -2(3) +7 => 6-6+7 = 7

(a+c)² = (3+4)² = 7² =49

3(6-3) +12 = 3(3) +12 = 9 +12 =21

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