Can you please explain the steps to solving this

Answer:
x=360
Step-By-Step Explanation:
x= a+102 + b+168
since a+b is 90,
x= 90+102+168
x= 360
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Answer:
Step-by-step explanation:
a+12= 12 added with a
90 = a + b (remeber this)
b+78= 78 added to b
a+120 = a +12+90
b + 168= 90 + b + 168
x= a +120 + b + 168
x= a + b + 120 + 168
x= (a + b) + 288
x= 90 + 288 ( cause we know that a + b = 90)
x = 378