Let's analyze and solve the problem step by step:
Step 1: Solve for x
The triangle △ABC is a right triangle. By the Pythagorean theorem:
AC2=AB2+BC2
From the diagram:
- AB=4
- BC=x+5
- AC=(x−1)+(x+5)=2x+4
Substituting these into the Pythagorean theorem:
(2x+4)2=42+(x+5)2
Expanding both sides:
(2x+4)2=4x2+16x+16
42=16,(x+5)2=x2+10x+25
The equation becomes:
4x2+16x+16=16+x2+10x+25
Simplify:
4x2+16x+16=x2+10x+41
Combine like terms:
4x2−x2+16x−10x+16−41=0
3x2+6x−25=0
Step 2: Solve the quadratic equation
Using the quadratic formula:
x=2a−b±b2−4ac
Here:
- a=3
- b=6
- c=−25
Substitute these values:
x=2(3)−6±62−4(3)(−25)
x=6−6±36+300
x=6−6±336
Simplify:
336=421
Thus:
x=6−6±421
Simplify further:
x=3−3±221
Choose the positive value for x (since it represents a length):
x=3−3+221
Step 3: Calculate E
The expression for E is:
E=tanθ+5⋅secθ
From the triangle:
- tanθ=ABBC=4x+5
- secθ=ABAC=42x+4
Substituting these:
E=4x+5+5⋅42x+4
Combine terms:
E=4x+5+5(2x+4)
Substitute x=3−3+221 into this expression to compute E.
Would you like me to evaluate this final step numerically?