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3 years ago

Elimination 4x+5y=-15 -3x-2y=13

1 answer:

4 0

Multiply the first equation by 3 and tge second by 4:
12x+15y=-45
-12x-8y=52
then add the equations:
0x+7y=7
7y=7
y=1
so 4x+5(1)=-15
4x+5=-15
4x=-20
x=-5

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Evaluate 1/3 - 5/6<br><br> I NEED THIS ASAP!!!

MissTica

Answer:

-1/2

Step-by-step explanation:

2/6 - 5/6= -3/6

= -1/2

4 0

3 years ago

Read 2 more answers

Please answer correctly and you will receive a crown and brainliest.

dlinn [17]

Answer:

See explanation

Step-by-step explanation:

Chevy Malibu hybrid = 6.8

Ford mustang = 9.6

Nissan Pathfinder = 10.8

Toyota Corolla = 6.3

1. Chevy Malibu hybrid to Toyota Corolla = 6.8 to 6.3

= 6.8 : 6.3

= 6.8 / 6.3

2. Nissan Pathfinder to Ford mustang = 10.8 to 9.6

= 10.8 : 9.6

= 10.8 / 9.6

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3. Toyota Corolla to Nissan Pathfinder = 6.3 to 10.8

= 6.3 : 10.8

= 6.3 / 10.8

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= 9.6 : 6.8

= 9.6 / 6.8

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6 0

3 years ago

A projectile is fired with muzzle speed 250 m/s and an angle of elevation 45° from a position 30 m above ground level. Where doe

qaws [65]

The projectile's horizontal and vertical positions at time $t$ are given by

$x=\left(250\dfrac{\rm m}{\rm s}\right)\cos45^\circ\,t$

$y=30\,\mathrm m+\left(250\dfrac{\rm m}{\rm s}\right)\sin45^\circ\,t-\dfrac g2t^2$

where $g=9.8\dfrac{\rm m}{\mathrm s^2}$ . Solve $y=0$ for the time $t$ it takes for the projectile to reach the ground:

$30+\dfrac{250}{\sqrt2}t-4.9t^2=0\implies t\approx36.2458\,\mathrm s$

In this time, the projectile will have traveled horizontally a distance of

$x=\dfrac{250\frac{\rm m}{\rm s}}{\sqrt2}(36.2458\,\mathrm s)\approx6400\,\mathrm m$

The projectile's horizontal and vertical velocities are given by

$v_x=\left(250\dfrac{\rm m}{\rm s}\right)\cos45^\circ$

$v_y=\left(250\dfrac{\rm m}{\rm s}\right)\sin45^\circ-gt$

At the time the projectile hits the ground, its velocity vector has horizontal component approx. 176.77 m/s and vertical component approx. -178.43 m/s, which corresponds to a speed of about $\sqrt{176.77^2+(-178.43)^2}\dfrac{\rm m}{\rm s}\approx250\dfrac{\rm m}{\rm s}$ .