Step-by-step explanation:
J=(x+4)²
K=(8-x)
X=5
=J+3k
=(x+4)(x+4)+3(8-x)
=(x²+8x+16+24-3x)
=25+25+40
=90
Alternatively:
J=(5+4)²
J=81
K=8-5
K=3
J+3k
81+3(3)
81+9
90
Expressions are problems with no answer. I would use it to represent inequalities and/or a basic formula
5+5= 10
por que 5 +5 es diez