Answer:
-4a^2+7a+4 , a=2 or -1/4
Step-by-step explanation:
Take -4 + 3a2 from 7a - a2
It means 7a -a^2 - (-4+3a^2)
7a -a^2 +4-3a^2
7a -a^2-3a^2+4
7a -4a^2+4
-4a^2+7a+4
-4a^2+8a-a+4
-4a^2-a+8a+4
-a(4a+1)+2(4a+1)
(-a+2)(4a+1) =0
-a+2=0 4a+1=0
-a=-2 4a=-1
-a/-1=-2/-1 a=-1/4
a=2 or -1/4
Let x + 15 = total penguins
15/ (x +15) = .30
15 = .30x + 4.5
.30x = 10.5
x = 35
Total penguins = 15 + 35 = 50
Double Check
15 / 50 * 100 = 30% Correct!!!
Answer:
Hence x = 60 and y = 50
e = 85 degrees
f = 158 degrees
Step-by-step explanation:
1) The sum of the interiror angle of the triangle is equal to the exterior
Given
Interior angles = y and 70
Exterior angle = 120 degrees
According to the law;
y + 70 = 120
y = 120-70
y = 50°
Sum of angle in the triangle is 180
x + y + 70 = 180
x + 50 + 70 = 180
x + 120 = 180
x = 180-120
x = 60
Hence x = 60 and y = 50
2) The sum of angles on a straight line is 180 degrees
40 + 55 + e = 180
95 + e = 180
e = 180 - 95
x = 85 degrees
3) Sum of angle at a point is 360 degrees
Hence 130 + 36.8 + 35.2 + f= 360
130 + 72 + f = 360
202 + f = 360
f = 360 - 202
f = 158 degrees
Answer: x=18
Step-by-step explanation: 16-18=-2
Good luck! :)