Answer:
1) 75 minutes / 1hour 15minutes
Step-by-step explanation:
to get one question done takes (45 ÷ 12) minutes. then times by 20.
Answer
2) I'm not too sure, I got 208.3 reoccurring, but that doesn't seem right so sorry if it's wrong
Answer
3)168 girls
step-by-step explanation
364 ÷ (6+7) × 6
Answer:
x = 13.5 units
Step-by-step explanation:
Segment drawn to join the two sides of the triangle is parallel to third side of the triangle.
Therefore, by basic proportionality theorem:
The answer would be A. When using Cramer's Rule to solve a system of equations, if the determinant of the coefficient matrix equals zero and neither numerator determinant is zero, then the system has infinite solutions. It would be hard finding this answer when we use the Cramer's Rule so instead we use the Gauss Elimination. Considering the equations:
x + y = 3 and <span>2x + 2y = 6
Determinant of the equations are </span>
<span>| 1 1 | </span>
<span>| 2 2 | = 0
</span>
the numerator determinants would be
<span>| 3 1 | . .| 1 3 | </span>
<span>| 6 2 | = | 2 6 | = 0.
Executing Gauss Elimination, any two numbers, whose sum is 3, would satisfy the given system. F</span>or instance (3, 0), <span>(2, 1) and (4, -1). Therefore, it would have infinitely many solutions. </span>
Answer:
t=+4.06
Step-by-step explanation:
when the baseball hits the ground, the height will be 0.
h=0we are given that h=−16t2+64t+4.
this means that the height is 0 when −16t2+64t+4=0.−16t2+64t+4=0divide both sides by 4:−4t2+16t+1=04=0−4t2+16t+1=0 can be solved using the quadratic formula:t=−b±√b2−4ac2a, where at2+bt+c=0.at2+bt+c=−4t2+16t+1a=−4,b=16,c=1t=−b+√b2−4ac2aor−b−√b2−4ac2a−b+√b2−4ac2a=−16+√272−8=−0.06..−b−√b2−4ac2a=−16−√272−8=4.06 (3s.f.)we have 2 values for t:−0.06 and 4.06.
since time cannot be negative, only the positive value can be taken.
this is 4.06, to 3 significant figures.the time taken is 4.06 seconds.
