Answer:
x ≈ - 5.32, x ≈ 1.32
Step-by-step explanation:
Given
x² + 4x - 7 = 0 ( add 7 to both sides )
x² + 4x = 7
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(2)x + 4 = 7 + 4
(x + 2)² = 11 ( take the square root of both sides )
x + 2 = ±
( subtract 2 from both sides )
x = - 2 ± 
Thus
x = - 2 -
≈ - 5.32 ( to 2 dec. places )
x = - 2 +
≈ 1.32 ( to 2 dec. places )
Answer:
876/7
Step-by-step explanation:
Just plug the number 5 into the equation and solve. Remember your Order of Operations (PEMDAS).
Answer:
Step-by-step explanation:
Split the polygon into 3 triangles as pictured below
<u>They have base and height:</u>
- 4 and 3, 1 and 1, 3 and 1
<u>Find the area of 3 triangles and add up:</u>
- A = 1/2*4*3 + 1/2*1*1 + 1/2*1*3 = 6 + 1/2 + 3/2 = 8 square units
From the identity,
sin^2(x)+cos^2(x)=1
then
cos(x)=sqrt(1-sin^2(x))
where sin(x) is given as 0.42.
Note that the above answer applies to 0<x<90 degrees