Answer:
x = 16
Step-by-step explanation:
The sum of measures of these three angles of any triangle is equal to 180 °
54 + 90 + (2x + 4) = 180
144 + 2x + 4 = 180
148 + 2x = 180
2x = 180 - 148
2x = 32

Answer:
23
Step-by-step explanation:
hey
Let the cost of the hair dryer equal x.
The net cost plus a 40% markup equals 42, set up an equation and solve forex.
1.4x = 42
Divide both sides by 1.4
X = 42 / 1.4
X = 30
The net cost was £30
Answer:
Step-by-step explanation:
x²+10x+21=0
x²+10x+(10/2)²-(10/2)²+21=0
x²+10x+25-25+21=0
(x+5)²-4=0
(x+5)²=4
(x+y)²=(x+y)(x+y)=x(x+y)+y(x+y)=x²+xy+xy+y²=x²+2xy+y²
(x+y)²=x²+2xy+y²
coefficient of x=2y
y²=[(coefficient of x)/2]²=(2y/2)²=y²